Add vendored packages back

lib/spack/external/_vendoring/_pyrsistent_version.py

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+__version__ = '0.18.0'

lib/spack/external/_vendoring/_pyrsistent_version.pyi

@@ -0,0 +1 @@
+from _pyrsistent_version import *

lib/spack/external/_vendoring/altgraph.pyi

@@ -0,0 +1 @@
+from altgraph import *

lib/spack/external/_vendoring/altgraph/Dot.py

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+"""
+altgraph.Dot - Interface to the dot language
+============================================
+
+The :py:mod:`~altgraph.Dot` module provides a simple interface to the
+file format used in the
+`graphviz <http://www.research.att.com/sw/tools/graphviz/>`_
+program. The module is intended to offload the most tedious part of the process
+(the **dot** file generation) while transparently exposing most of its
+features.
+
+To display the graphs or to generate image files the
+`graphviz <http://www.research.att.com/sw/tools/graphviz/>`_
+package needs to be installed on the system, moreover the :command:`dot` and
+:command:`dotty` programs must be accesible in the program path so that they
+can be ran from processes spawned within the module.
+
+Example usage
+-------------
+
+Here is a typical usage::
+
+    from altgraph import Graph, Dot
+
+    # create a graph
+    edges = [ (1,2), (1,3), (3,4), (3,5), (4,5), (5,4) ]
+    graph = Graph.Graph(edges)
+
+    # create a dot representation of the graph
+    dot = Dot.Dot(graph)
+
+    # display the graph
+    dot.display()
+
+    # save the dot representation into the mydot.dot file
+    dot.save_dot(file_name='mydot.dot')
+
+    # save dot file as gif image into the graph.gif file
+    dot.save_img(file_name='graph', file_type='gif')
+
+Directed graph and non-directed graph
+-------------------------------------
+
+Dot class can use for both directed graph and non-directed graph
+by passing ``graphtype`` parameter.
+
+Example::
+
+    # create directed graph(default)
+    dot = Dot.Dot(graph, graphtype="digraph")
+
+    # create non-directed graph
+    dot = Dot.Dot(graph, graphtype="graph")
+
+Customizing the output
+----------------------
+
+The graph drawing process may be customized by passing
+valid :command:`dot` parameters for the nodes and edges. For a list of all
+parameters see the `graphviz <http://www.research.att.com/sw/tools/graphviz/>`_
+documentation.
+
+Example::
+
+    # customizing the way the overall graph is drawn
+    dot.style(size='10,10', rankdir='RL', page='5, 5' , ranksep=0.75)
+
+    # customizing node drawing
+    dot.node_style(1, label='BASE_NODE',shape='box', color='blue' )
+    dot.node_style(2, style='filled', fillcolor='red')
+
+    # customizing edge drawing
+    dot.edge_style(1, 2, style='dotted')
+    dot.edge_style(3, 5, arrowhead='dot', label='binds', labelangle='90')
+    dot.edge_style(4, 5, arrowsize=2, style='bold')
+
+
+.. note::
+
+   dotty (invoked via :py:func:`~altgraph.Dot.display`) may not be able to
+   display all graphics styles. To verify the output save it to an image file
+   and look at it that way.
+
+Valid attributes
+----------------
+
+    - dot styles, passed via the :py:meth:`Dot.style` method::
+
+        rankdir = 'LR'   (draws the graph horizontally, left to right)
+        ranksep = number (rank separation in inches)
+
+    - node attributes, passed via the :py:meth:`Dot.node_style` method::
+
+        style = 'filled' | 'invisible' | 'diagonals' | 'rounded'
+        shape = 'box' | 'ellipse' | 'circle' | 'point' | 'triangle'
+
+    - edge attributes, passed via the :py:meth:`Dot.edge_style` method::
+
+        style     = 'dashed' | 'dotted' | 'solid' | 'invis' | 'bold'
+        arrowhead = 'box' | 'crow' | 'diamond' | 'dot' | 'inv' | 'none'
+            | 'tee' | 'vee'
+        weight    = number (the larger the number the closer the nodes will be)
+
+    - valid `graphviz colors
+        <http://www.research.att.com/~erg/graphviz/info/colors.html>`_
+
+    - for more details on how to control the graph drawing process see the
+      `graphviz reference
+        <http://www.research.att.com/sw/tools/graphviz/refs.html>`_.
+"""
+import os
+import warnings
+
+from altgraph import GraphError
+
+
+class Dot(object):
+    """
+    A  class providing a **graphviz** (dot language) representation
+    allowing a fine grained control over how the graph is being
+    displayed.
+
+    If the :command:`dot` and :command:`dotty` programs are not in the current
+    system path their location needs to be specified in the contructor.
+    """
+
+    def __init__(
+        self,
+        graph=None,
+        nodes=None,
+        edgefn=None,
+        nodevisitor=None,
+        edgevisitor=None,
+        name="G",
+        dot="dot",
+        dotty="dotty",
+        neato="neato",
+        graphtype="digraph",
+    ):
+        """
+        Initialization.
+        """
+        self.name, self.attr = name, {}
+
+        assert graphtype in ["graph", "digraph"]
+        self.type = graphtype
+
+        self.temp_dot = "tmp_dot.dot"
+        self.temp_neo = "tmp_neo.dot"
+
+        self.dot, self.dotty, self.neato = dot, dotty, neato
+
+        # self.nodes: node styles
+        # self.edges: edge styles
+        self.nodes, self.edges = {}, {}
+
+        if graph is not None and nodes is None:
+            nodes = graph
+        if graph is not None and edgefn is None:
+
+            def edgefn(node, graph=graph):
+                return graph.out_nbrs(node)
+
+        if nodes is None:
+            nodes = ()
+
+        seen = set()
+        for node in nodes:
+            if nodevisitor is None:
+                style = {}
+            else:
+                style = nodevisitor(node)
+            if style is not None:
+                self.nodes[node] = {}
+                self.node_style(node, **style)
+                seen.add(node)
+        if edgefn is not None:
+            for head in seen:
+                for tail in (n for n in edgefn(head) if n in seen):
+                    if edgevisitor is None:
+                        edgestyle = {}
+                    else:
+                        edgestyle = edgevisitor(head, tail)
+                    if edgestyle is not None:
+                        if head not in self.edges:
+                            self.edges[head] = {}
+                        self.edges[head][tail] = {}
+                        self.edge_style(head, tail, **edgestyle)
+
+    def style(self, **attr):
+        """
+        Changes the overall style
+        """
+        self.attr = attr
+
+    def display(self, mode="dot"):
+        """
+        Displays the current graph via dotty
+        """
+
+        if mode == "neato":
+            self.save_dot(self.temp_neo)
+            neato_cmd = "%s -o %s %s" % (self.neato, self.temp_dot, self.temp_neo)
+            os.system(neato_cmd)
+        else:
+            self.save_dot(self.temp_dot)
+
+        plot_cmd = "%s %s" % (self.dotty, self.temp_dot)
+        os.system(plot_cmd)
+
+    def node_style(self, node, **kwargs):
+        """
+        Modifies a node style to the dot representation.
+        """
+        if node not in self.edges:
+            self.edges[node] = {}
+        self.nodes[node] = kwargs
+
+    def all_node_style(self, **kwargs):
+        """
+        Modifies all node styles
+        """
+        for node in self.nodes:
+            self.node_style(node, **kwargs)
+
+    def edge_style(self, head, tail, **kwargs):
+        """
+        Modifies an edge style to the dot representation.
+        """
+        if tail not in self.nodes:
+            raise GraphError("invalid node %s" % (tail,))
+
+        try:
+            if tail not in self.edges[head]:
+                self.edges[head][tail] = {}
+            self.edges[head][tail] = kwargs
+        except KeyError:
+            raise GraphError("invalid edge  %s -> %s " % (head, tail))
+
+    def iterdot(self):
+        # write graph title
+        if self.type == "digraph":
+            yield "digraph %s {\n" % (self.name,)
+        elif self.type == "graph":
+            yield "graph %s {\n" % (self.name,)
+
+        else:
+            raise GraphError("unsupported graphtype %s" % (self.type,))
+
+        # write overall graph attributes
+        for attr_name, attr_value in sorted(self.attr.items()):
+            yield '%s="%s";' % (attr_name, attr_value)
+        yield "\n"
+
+        # some reusable patterns
+        cpatt = '%s="%s",'  # to separate attributes
+        epatt = "];\n"  # to end attributes
+
+        # write node attributes
+        for node_name, node_attr in sorted(self.nodes.items()):
+            yield '\t"%s" [' % (node_name,)
+            for attr_name, attr_value in sorted(node_attr.items()):
+                yield cpatt % (attr_name, attr_value)
+            yield epatt
+
+        # write edge attributes
+        for head in sorted(self.edges):
+            for tail in sorted(self.edges[head]):
+                if self.type == "digraph":
+                    yield '\t"%s" -> "%s" [' % (head, tail)
+                else:
+                    yield '\t"%s" -- "%s" [' % (head, tail)
+                for attr_name, attr_value in sorted(self.edges[head][tail].items()):
+                    yield cpatt % (attr_name, attr_value)
+                yield epatt
+
+        # finish file
+        yield "}\n"
+
+    def __iter__(self):
+        return self.iterdot()
+
+    def save_dot(self, file_name=None):
+        """
+        Saves the current graph representation into a file
+        """
+
+        if not file_name:
+            warnings.warn(DeprecationWarning, "always pass a file_name")
+            file_name = self.temp_dot
+
+        with open(file_name, "w") as fp:
+            for chunk in self.iterdot():
+                fp.write(chunk)
+
+    def save_img(self, file_name=None, file_type="gif", mode="dot"):
+        """
+        Saves the dot file as an image file
+        """
+
+        if not file_name:
+            warnings.warn(DeprecationWarning, "always pass a file_name")
+            file_name = "out"
+
+        if mode == "neato":
+            self.save_dot(self.temp_neo)
+            neato_cmd = "%s -o %s %s" % (self.neato, self.temp_dot, self.temp_neo)
+            os.system(neato_cmd)
+            plot_cmd = self.dot
+        else:
+            self.save_dot(self.temp_dot)
+            plot_cmd = self.dot
+
+        file_name = "%s.%s" % (file_name, file_type)
+        create_cmd = "%s -T%s %s -o %s" % (
+            plot_cmd,
+            file_type,
+            self.temp_dot,
+            file_name,
+        )
+        os.system(create_cmd)

lib/spack/external/_vendoring/altgraph/Graph.py

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+"""
+altgraph.Graph - Base Graph class
+=================================
+
+..
+  #--Version 2.1
+  #--Bob Ippolito October, 2004
+
+  #--Version 2.0
+  #--Istvan Albert June, 2004
+
+  #--Version 1.0
+  #--Nathan Denny, May 27, 1999
+"""
+
+from collections import deque
+
+from altgraph import GraphError
+
+
+class Graph(object):
+    """
+    The Graph class represents a directed graph with *N* nodes and *E* edges.
+
+    Naming conventions:
+
+    - the prefixes such as *out*, *inc* and *all* will refer to methods
+      that operate on the outgoing, incoming or all edges of that node.
+
+      For example: :py:meth:`inc_degree` will refer to the degree of the node
+      computed over the incoming edges (the number of neighbours linking to
+      the node).
+
+    - the prefixes such as *forw* and *back* will refer to the
+      orientation of the edges used in the method with respect to the node.
+
+      For example: :py:meth:`forw_bfs` will start at the node then use the
+      outgoing edges to traverse the graph (goes forward).
+    """
+
+    def __init__(self, edges=None):
+        """
+        Initialization
+        """
+
+        self.next_edge = 0
+        self.nodes, self.edges = {}, {}
+        self.hidden_edges, self.hidden_nodes = {}, {}
+
+        if edges is not None:
+            for item in edges:
+                if len(item) == 2:
+                    head, tail = item
+                    self.add_edge(head, tail)
+                elif len(item) == 3:
+                    head, tail, data = item
+                    self.add_edge(head, tail, data)
+                else:
+                    raise GraphError("Cannot create edge from %s" % (item,))
+
+    def __repr__(self):
+        return "<Graph: %d nodes, %d edges>" % (
+            self.number_of_nodes(),
+            self.number_of_edges(),
+        )
+
+    def add_node(self, node, node_data=None):
+        """
+        Adds a new node to the graph.  Arbitrary data can be attached to the
+        node via the node_data parameter.  Adding the same node twice will be
+        silently ignored.
+
+        The node must be a hashable value.
+        """
+        #
+        # the nodes will contain tuples that will store incoming edges,
+        # outgoing edges and data
+        #
+        # index 0 -> incoming edges
+        # index 1 -> outgoing edges
+
+        if node in self.hidden_nodes:
+            # Node is present, but hidden
+            return
+
+        if node not in self.nodes:
+            self.nodes[node] = ([], [], node_data)
+
+    def add_edge(self, head_id, tail_id, edge_data=1, create_nodes=True):
+        """
+        Adds a directed edge going from head_id to tail_id.
+        Arbitrary data can be attached to the edge via edge_data.
+        It may create the nodes if adding edges between nonexisting ones.
+
+        :param head_id: head node
+        :param tail_id: tail node
+        :param edge_data: (optional) data attached to the edge
+        :param create_nodes: (optional) creates the head_id or tail_id
+            node in case they did not exist
+        """
+        # shorcut
+        edge = self.next_edge
+
+        # add nodes if on automatic node creation
+        if create_nodes:
+            self.add_node(head_id)
+            self.add_node(tail_id)
+
+        # update the corresponding incoming and outgoing lists in the nodes
+        # index 0 -> incoming edges
+        # index 1 -> outgoing edges
+
+        try:
+            self.nodes[tail_id][0].append(edge)
+            self.nodes[head_id][1].append(edge)
+        except KeyError:
+            raise GraphError("Invalid nodes %s -> %s" % (head_id, tail_id))
+
+        # store edge information
+        self.edges[edge] = (head_id, tail_id, edge_data)
+
+        self.next_edge += 1
+
+    def hide_edge(self, edge):
+        """
+        Hides an edge from the graph. The edge may be unhidden at some later
+        time.
+        """
+        try:
+            head_id, tail_id, edge_data = self.hidden_edges[edge] = self.edges[edge]
+            self.nodes[tail_id][0].remove(edge)
+            self.nodes[head_id][1].remove(edge)
+            del self.edges[edge]
+        except KeyError:
+            raise GraphError("Invalid edge %s" % edge)
+
+    def hide_node(self, node):
+        """
+        Hides a node from the graph.  The incoming and outgoing edges of the
+        node will also be hidden.  The node may be unhidden at some later time.
+        """
+        try:
+            all_edges = self.all_edges(node)
+            self.hidden_nodes[node] = (self.nodes[node], all_edges)
+            for edge in all_edges:
+                self.hide_edge(edge)
+            del self.nodes[node]
+        except KeyError:
+            raise GraphError("Invalid node %s" % node)
+
+    def restore_node(self, node):
+        """
+        Restores a previously hidden node back into the graph and restores
+        all of its incoming and outgoing edges.
+        """
+        try:
+            self.nodes[node], all_edges = self.hidden_nodes[node]
+            for edge in all_edges:
+                self.restore_edge(edge)
+            del self.hidden_nodes[node]
+        except KeyError:
+            raise GraphError("Invalid node %s" % node)
+
+    def restore_edge(self, edge):
+        """
+        Restores a previously hidden edge back into the graph.
+        """
+        try:
+            head_id, tail_id, data = self.hidden_edges[edge]
+            self.nodes[tail_id][0].append(edge)
+            self.nodes[head_id][1].append(edge)
+            self.edges[edge] = head_id, tail_id, data
+            del self.hidden_edges[edge]
+        except KeyError:
+            raise GraphError("Invalid edge %s" % edge)
+
+    def restore_all_edges(self):
+        """
+        Restores all hidden edges.
+        """
+        for edge in list(self.hidden_edges.keys()):
+            try:
+                self.restore_edge(edge)
+            except GraphError:
+                pass
+
+    def restore_all_nodes(self):
+        """
+        Restores all hidden nodes.
+        """
+        for node in list(self.hidden_nodes.keys()):
+            self.restore_node(node)
+
+    def __contains__(self, node):
+        """
+        Test whether a node is in the graph
+        """
+        return node in self.nodes
+
+    def edge_by_id(self, edge):
+        """
+        Returns the edge that connects the head_id and tail_id nodes
+        """
+        try:
+            head, tail, data = self.edges[edge]
+        except KeyError:
+            head, tail = None, None
+            raise GraphError("Invalid edge %s" % edge)
+
+        return (head, tail)
+
+    def edge_by_node(self, head, tail):
+        """
+        Returns the edge that connects the head_id and tail_id nodes
+        """
+        for edge in self.out_edges(head):
+            if self.tail(edge) == tail:
+                return edge
+        return None
+
+    def number_of_nodes(self):
+        """
+        Returns the number of nodes
+        """
+        return len(self.nodes)
+
+    def number_of_edges(self):
+        """
+        Returns the number of edges
+        """
+        return len(self.edges)
+
+    def __iter__(self):
+        """
+        Iterates over all nodes in the graph
+        """
+        return iter(self.nodes)
+
+    def node_list(self):
+        """
+        Return a list of the node ids for all visible nodes in the graph.
+        """
+        return list(self.nodes.keys())
+
+    def edge_list(self):
+        """
+        Returns an iterator for all visible nodes in the graph.
+        """
+        return list(self.edges.keys())
+
+    def number_of_hidden_edges(self):
+        """
+        Returns the number of hidden edges
+        """
+        return len(self.hidden_edges)
+
+    def number_of_hidden_nodes(self):
+        """
+        Returns the number of hidden nodes
+        """
+        return len(self.hidden_nodes)
+
+    def hidden_node_list(self):
+        """
+        Returns the list with the hidden nodes
+        """
+        return list(self.hidden_nodes.keys())
+
+    def hidden_edge_list(self):
+        """
+        Returns a list with the hidden edges
+        """
+        return list(self.hidden_edges.keys())
+
+    def describe_node(self, node):
+        """
+        return node, node data, outgoing edges, incoming edges for node
+        """
+        incoming, outgoing, data = self.nodes[node]
+        return node, data, outgoing, incoming
+
+    def describe_edge(self, edge):
+        """
+        return edge, edge data, head, tail for edge
+        """
+        head, tail, data = self.edges[edge]
+        return edge, data, head, tail
+
+    def node_data(self, node):
+        """
+        Returns the data associated with a node
+        """
+        return self.nodes[node][2]
+
+    def edge_data(self, edge):
+        """
+        Returns the data associated with an edge
+        """
+        return self.edges[edge][2]
+
+    def update_edge_data(self, edge, edge_data):
+        """
+        Replace the edge data for a specific edge
+        """
+        self.edges[edge] = self.edges[edge][0:2] + (edge_data,)
+
+    def head(self, edge):
+        """
+        Returns the node of the head of the edge.
+        """
+        return self.edges[edge][0]
+
+    def tail(self, edge):
+        """
+        Returns node of the tail of the edge.
+        """
+        return self.edges[edge][1]
+
+    def out_nbrs(self, node):
+        """
+        List of nodes connected by outgoing edges
+        """
+        return [self.tail(n) for n in self.out_edges(node)]
+
+    def inc_nbrs(self, node):
+        """
+        List of nodes connected by incoming edges
+        """
+        return [self.head(n) for n in self.inc_edges(node)]
+
+    def all_nbrs(self, node):
+        """
+        List of nodes connected by incoming and outgoing edges
+        """
+        return list(dict.fromkeys(self.inc_nbrs(node) + self.out_nbrs(node)))
+
+    def out_edges(self, node):
+        """
+        Returns a list of the outgoing edges
+        """
+        try:
+            return list(self.nodes[node][1])
+        except KeyError:
+            raise GraphError("Invalid node %s" % node)
+
+    def inc_edges(self, node):
+        """
+        Returns a list of the incoming edges
+        """
+        try:
+            return list(self.nodes[node][0])
+        except KeyError:
+            raise GraphError("Invalid node %s" % node)
+
+    def all_edges(self, node):
+        """
+        Returns a list of incoming and outging edges.
+        """
+        return set(self.inc_edges(node) + self.out_edges(node))
+
+    def out_degree(self, node):
+        """
+        Returns the number of outgoing edges
+        """
+        return len(self.out_edges(node))
+
+    def inc_degree(self, node):
+        """
+        Returns the number of incoming edges
+        """
+        return len(self.inc_edges(node))
+
+    def all_degree(self, node):
+        """
+        The total degree of a node
+        """
+        return self.inc_degree(node) + self.out_degree(node)
+
+    def _topo_sort(self, forward=True):
+        """
+        Topological sort.
+
+        Returns a list of nodes where the successors (based on outgoing and
+        incoming edges selected by the forward parameter) of any given node
+        appear in the sequence after that node.
+        """
+        topo_list = []
+        queue = deque()
+        indeg = {}
+
+        # select the operation that will be performed
+        if forward:
+            get_edges = self.out_edges
+            get_degree = self.inc_degree
+            get_next = self.tail
+        else:
+            get_edges = self.inc_edges
+            get_degree = self.out_degree
+            get_next = self.head
+
+        for node in self.node_list():
+            degree = get_degree(node)
+            if degree:
+                indeg[node] = degree
+            else:
+                queue.append(node)
+
+        while queue:
+            curr_node = queue.popleft()
+            topo_list.append(curr_node)
+            for edge in get_edges(curr_node):
+                tail_id = get_next(edge)
+                if tail_id in indeg:
+                    indeg[tail_id] -= 1
+                    if indeg[tail_id] == 0:
+                        queue.append(tail_id)
+
+        if len(topo_list) == len(self.node_list()):
+            valid = True
+        else:
+            # the graph has cycles, invalid topological sort
+            valid = False
+
+        return (valid, topo_list)
+
+    def forw_topo_sort(self):
+        """
+        Topological sort.
+
+        Returns a list of nodes where the successors (based on outgoing edges)
+        of any given node appear in the sequence after that node.
+        """
+        return self._topo_sort(forward=True)
+
+    def back_topo_sort(self):
+        """
+        Reverse topological sort.
+
+        Returns a list of nodes where the successors (based on incoming edges)
+        of any given node appear in the sequence after that node.
+        """
+        return self._topo_sort(forward=False)
+
+    def _bfs_subgraph(self, start_id, forward=True):
+        """
+        Private method creates a subgraph in a bfs order.
+
+        The forward parameter specifies whether it is a forward or backward
+        traversal.
+        """
+        if forward:
+            get_bfs = self.forw_bfs
+            get_nbrs = self.out_nbrs
+        else:
+            get_bfs = self.back_bfs
+            get_nbrs = self.inc_nbrs
+
+        g = Graph()
+        bfs_list = get_bfs(start_id)
+        for node in bfs_list:
+            g.add_node(node)
+
+        for node in bfs_list:
+            for nbr_id in get_nbrs(node):
+                if forward:
+                    g.add_edge(node, nbr_id)
+                else:
+                    g.add_edge(nbr_id, node)
+
+        return g
+
+    def forw_bfs_subgraph(self, start_id):
+        """
+        Creates and returns a subgraph consisting of the breadth first
+        reachable nodes based on their outgoing edges.
+        """
+        return self._bfs_subgraph(start_id, forward=True)
+
+    def back_bfs_subgraph(self, start_id):
+        """
+        Creates and returns a subgraph consisting of the breadth first
+        reachable nodes based on the incoming edges.
+        """
+        return self._bfs_subgraph(start_id, forward=False)
+
+    def iterdfs(self, start, end=None, forward=True):
+        """
+        Collecting nodes in some depth first traversal.
+
+        The forward parameter specifies whether it is a forward or backward
+        traversal.
+        """
+        visited, stack = {start}, deque([start])
+
+        if forward:
+            get_edges = self.out_edges
+            get_next = self.tail
+        else:
+            get_edges = self.inc_edges
+            get_next = self.head
+
+        while stack:
+            curr_node = stack.pop()
+            yield curr_node
+            if curr_node == end:
+                break
+            for edge in sorted(get_edges(curr_node)):
+                tail = get_next(edge)
+                if tail not in visited:
+                    visited.add(tail)
+                    stack.append(tail)
+
+    def iterdata(self, start, end=None, forward=True, condition=None):
+        """
+        Perform a depth-first walk of the graph (as ``iterdfs``)
+        and yield the item data of every node where condition matches. The
+        condition callback is only called when node_data is not None.
+        """
+
+        visited, stack = {start}, deque([start])
+
+        if forward:
+            get_edges = self.out_edges
+            get_next = self.tail
+        else:
+            get_edges = self.inc_edges
+            get_next = self.head
+
+        get_data = self.node_data
+
+        while stack:
+            curr_node = stack.pop()
+            curr_data = get_data(curr_node)
+            if curr_data is not None:
+                if condition is not None and not condition(curr_data):
+                    continue
+                yield curr_data
+            if curr_node == end:
+                break
+            for edge in get_edges(curr_node):
+                tail = get_next(edge)
+                if tail not in visited:
+                    visited.add(tail)
+                    stack.append(tail)
+
+    def _iterbfs(self, start, end=None, forward=True):
+        """
+        The forward parameter specifies whether it is a forward or backward
+        traversal.  Returns a list of tuples where the first value is the hop
+        value the second value is the node id.
+        """
+        queue, visited = deque([(start, 0)]), {start}
+
+        # the direction of the bfs depends on the edges that are sampled
+        if forward:
+            get_edges = self.out_edges
+            get_next = self.tail
+        else:
+            get_edges = self.inc_edges
+            get_next = self.head
+
+        while queue:
+            curr_node, curr_step = queue.popleft()
+            yield (curr_node, curr_step)
+            if curr_node == end:
+                break
+            for edge in get_edges(curr_node):
+                tail = get_next(edge)
+                if tail not in visited:
+                    visited.add(tail)
+                    queue.append((tail, curr_step + 1))
+
+    def forw_bfs(self, start, end=None):
+        """
+        Returns a list of nodes in some forward BFS order.
+
+        Starting from the start node the breadth first search proceeds along
+        outgoing edges.
+        """
+        return [node for node, step in self._iterbfs(start, end, forward=True)]
+
+    def back_bfs(self, start, end=None):
+        """
+        Returns a list of nodes in some backward BFS order.
+
+        Starting from the start node the breadth first search proceeds along
+        incoming edges.
+        """
+        return [node for node, _ in self._iterbfs(start, end, forward=False)]
+
+    def forw_dfs(self, start, end=None):
+        """
+        Returns a list of nodes in some forward DFS order.
+
+        Starting with the start node the depth first search proceeds along
+        outgoing edges.
+        """
+        return list(self.iterdfs(start, end, forward=True))
+
+    def back_dfs(self, start, end=None):
+        """
+        Returns a list of nodes in some backward DFS order.
+
+        Starting from the start node the depth first search proceeds along
+        incoming edges.
+        """
+        return list(self.iterdfs(start, end, forward=False))
+
+    def connected(self):
+        """
+        Returns :py:data:`True` if the graph's every node can be reached from
+        every other node.
+        """
+        node_list = self.node_list()
+        for node in node_list:
+            bfs_list = self.forw_bfs(node)
+            if len(bfs_list) != len(node_list):
+                return False
+        return True
+
+    def clust_coef(self, node):
+        """
+        Computes and returns the local clustering coefficient of node.
+
+        The local cluster coefficient is proportion of the actual number of
+        edges between neighbours of node and the maximum number of edges
+        between those neighbours.
+
+        See "Local Clustering Coefficient" on
+        <http://en.wikipedia.org/wiki/Clustering_coefficient>
+        for a formal definition.
+        """
+        num = 0
+        nbr_set = set(self.out_nbrs(node))
+
+        if node in nbr_set:
+            nbr_set.remove(node)  # loop defense
+
+        for nbr in nbr_set:
+            sec_set = set(self.out_nbrs(nbr))
+            if nbr in sec_set:
+                sec_set.remove(nbr)  # loop defense
+            num += len(nbr_set & sec_set)
+
+        nbr_num = len(nbr_set)
+        if nbr_num:
+            clust_coef = float(num) / (nbr_num * (nbr_num - 1))
+        else:
+            clust_coef = 0.0
+        return clust_coef
+
+    def get_hops(self, start, end=None, forward=True):
+        """
+        Computes the hop distance to all nodes centered around a node.
+
+        First order neighbours are at hop 1, their neigbours are at hop 2 etc.
+        Uses :py:meth:`forw_bfs` or :py:meth:`back_bfs` depending on the value
+        of the forward parameter.  If the distance between all neighbouring
+        nodes is 1 the hop number corresponds to the shortest distance between
+        the nodes.
+
+        :param start: the starting node
+        :param end: ending node (optional). When not specified will search the
+            whole graph.
+        :param forward: directionality parameter (optional).
+            If C{True} (default) it uses L{forw_bfs} otherwise L{back_bfs}.
+        :return: returns a list of tuples where each tuple contains the
+            node and the hop.
+
+        Typical usage::
+
+            >>> print (graph.get_hops(1, 8))
+            >>> [(1, 0), (2, 1), (3, 1), (4, 2), (5, 3), (7, 4), (8, 5)]
+            # node 1 is at 0 hops
+            # node 2 is at 1 hop
+            # ...
+            # node 8 is at 5 hops
+        """
+        if forward:
+            return list(self._iterbfs(start=start, end=end, forward=True))
+        else:
+            return list(self._iterbfs(start=start, end=end, forward=False))

lib/spack/external/_vendoring/altgraph/GraphAlgo.py

@@ -0,0 +1,171 @@
+"""
+altgraph.GraphAlgo - Graph algorithms
+=====================================
+"""
+from altgraph import GraphError
+
+
+def dijkstra(graph, start, end=None):
+    """
+    Dijkstra's algorithm for shortest paths
+
+    `David Eppstein, UC Irvine, 4 April 2002
+        <http://www.ics.uci.edu/~eppstein/161/python/>`_
+
+    `Python Cookbook Recipe
+        <http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/119466>`_
+
+    Find shortest paths from the  start node to all nodes nearer than or
+    equal to the end node.
+
+    Dijkstra's algorithm is only guaranteed to work correctly when all edge
+    lengths are positive.  This code does not verify this property for all
+    edges (only the edges examined until the end vertex is reached), but will
+    correctly compute shortest paths even for some graphs with negative edges,
+    and will raise an exception if it discovers that a negative edge has
+    caused it to make a mistake.
+
+    Adapted to altgraph by Istvan Albert, Pennsylvania State University -
+    June, 9 2004
+    """
+    D = {}  # dictionary of final distances
+    P = {}  # dictionary of predecessors
+    Q = _priorityDictionary()  # estimated distances of non-final vertices
+    Q[start] = 0
+
+    for v in Q:
+        D[v] = Q[v]
+        if v == end:
+            break
+
+        for w in graph.out_nbrs(v):
+            edge_id = graph.edge_by_node(v, w)
+            vwLength = D[v] + graph.edge_data(edge_id)
+            if w in D:
+                if vwLength < D[w]:
+                    raise GraphError(
+                        "Dijkstra: found better path to already-final vertex"
+                    )
+            elif w not in Q or vwLength < Q[w]:
+                Q[w] = vwLength
+                P[w] = v
+
+    return (D, P)
+
+
+def shortest_path(graph, start, end):
+    """
+    Find a single shortest path from the *start* node to the *end* node.
+    The input has the same conventions as dijkstra(). The output is a list of
+    the nodes in order along the shortest path.
+
+    **Note that the distances must be stored in the edge data as numeric data**
+    """
+
+    D, P = dijkstra(graph, start, end)
+    Path = []
+    while 1:
+        Path.append(end)
+        if end == start:
+            break
+        end = P[end]
+    Path.reverse()
+    return Path
+
+
+#
+# Utility classes and functions
+#
+class _priorityDictionary(dict):
+    """
+    Priority dictionary using binary heaps (internal use only)
+
+    David Eppstein, UC Irvine, 8 Mar 2002
+
+    Implements a data structure that acts almost like a dictionary, with
+    two modifications:
+
+        1. D.smallest() returns the value x minimizing D[x].  For this to
+           work correctly, all values D[x] stored in the dictionary must be
+           comparable.
+
+        2. iterating "for x in D" finds and removes the items from D in sorted
+           order. Each item is not removed until the next item is requested,
+           so D[x] will still return a useful value until the next iteration
+           of the for-loop.  Each operation takes logarithmic amortized time.
+    """
+
+    def __init__(self):
+        """
+        Initialize priorityDictionary by creating binary heap of pairs
+        (value,key).  Note that changing or removing a dict entry will not
+        remove the old pair from the heap until it is found by smallest()
+        or until the heap is rebuilt.
+        """
+        self.__heap = []
+        dict.__init__(self)
+
+    def smallest(self):
+        """
+        Find smallest item after removing deleted items from front of heap.
+        """
+        if len(self) == 0:
+            raise IndexError("smallest of empty priorityDictionary")
+        heap = self.__heap
+        while heap[0][1] not in self or self[heap[0][1]] != heap[0][0]:
+            lastItem = heap.pop()
+            insertionPoint = 0
+            while 1:
+                smallChild = 2 * insertionPoint + 1
+                if (
+                    smallChild + 1 < len(heap)
+                    and heap[smallChild] > heap[smallChild + 1]
+                ):
+                    smallChild += 1
+                if smallChild >= len(heap) or lastItem <= heap[smallChild]:
+                    heap[insertionPoint] = lastItem
+                    break
+                heap[insertionPoint] = heap[smallChild]
+                insertionPoint = smallChild
+        return heap[0][1]
+
+    def __iter__(self):
+        """
+        Create destructive sorted iterator of priorityDictionary.
+        """
+
+        def iterfn():
+            while len(self) > 0:
+                x = self.smallest()
+                yield x
+                del self[x]
+
+        return iterfn()
+
+    def __setitem__(self, key, val):
+        """
+        Change value stored in dictionary and add corresponding pair to heap.
+        Rebuilds the heap if the number of deleted items gets large, to avoid
+        memory leakage.
+        """
+        dict.__setitem__(self, key, val)
+        heap = self.__heap
+        if len(heap) > 2 * len(self):
+            self.__heap = [(v, k) for k, v in self.items()]
+            self.__heap.sort()
+        else:
+            newPair = (val, key)
+            insertionPoint = len(heap)
+            heap.append(None)
+            while insertionPoint > 0 and newPair < heap[(insertionPoint - 1) // 2]:
+                heap[insertionPoint] = heap[(insertionPoint - 1) // 2]
+                insertionPoint = (insertionPoint - 1) // 2
+            heap[insertionPoint] = newPair
+
+    def setdefault(self, key, val):
+        """
+        Reimplement setdefault to pass through our customized __setitem__.
+        """
+        if key not in self:
+            self[key] = val
+        return self[key]

lib/spack/external/_vendoring/altgraph/GraphStat.py

@@ -0,0 +1,73 @@
+"""
+altgraph.GraphStat - Functions providing various graph statistics
+=================================================================
+"""
+
+
+def degree_dist(graph, limits=(0, 0), bin_num=10, mode="out"):
+    """
+    Computes the degree distribution for a graph.
+
+    Returns a list of tuples where the first element of the tuple is the
+    center of the bin representing a range of degrees and the second element
+    of the tuple are the number of nodes with the degree falling in the range.
+
+    Example::
+
+        ....
+    """
+
+    deg = []
+    if mode == "inc":
+        get_deg = graph.inc_degree
+    else:
+        get_deg = graph.out_degree
+
+    for node in graph:
+        deg.append(get_deg(node))
+
+    if not deg:
+        return []
+
+    results = _binning(values=deg, limits=limits, bin_num=bin_num)
+
+    return results
+
+
+_EPS = 1.0 / (2.0 ** 32)
+
+
+def _binning(values, limits=(0, 0), bin_num=10):
+    """
+    Bins data that falls between certain limits, if the limits are (0, 0) the
+    minimum and maximum values are used.
+
+    Returns a list of tuples where the first element of the tuple is the
+    center of the bin and the second element of the tuple are the counts.
+    """
+    if limits == (0, 0):
+        min_val, max_val = min(values) - _EPS, max(values) + _EPS
+    else:
+        min_val, max_val = limits
+
+    # get bin size
+    bin_size = (max_val - min_val) / float(bin_num)
+    bins = [0] * (bin_num)
+
+    # will ignore these outliers for now
+    for value in values:
+        try:
+            if (value - min_val) >= 0:
+                index = int((value - min_val) / float(bin_size))
+                bins[index] += 1
+        except IndexError:
+            pass
+
+    # make it ready for an x,y plot
+    result = []
+    center = (bin_size / 2) + min_val
+    for i, y in enumerate(bins):
+        x = center + bin_size * i
+        result.append((x, y))
+
+    return result

lib/spack/external/_vendoring/altgraph/GraphUtil.py

@@ -0,0 +1,139 @@
+"""
+altgraph.GraphUtil - Utility classes and functions
+==================================================
+"""
+
+import random
+from collections import deque
+
+from altgraph import Graph, GraphError
+
+
+def generate_random_graph(node_num, edge_num, self_loops=False, multi_edges=False):
+    """
+    Generates and returns a :py:class:`~altgraph.Graph.Graph` instance with
+    *node_num* nodes randomly connected by *edge_num* edges.
+    """
+    g = Graph.Graph()
+
+    if not multi_edges:
+        if self_loops:
+            max_edges = node_num * node_num
+        else:
+            max_edges = node_num * (node_num - 1)
+
+        if edge_num > max_edges:
+            raise GraphError("inconsistent arguments to 'generate_random_graph'")
+
+    nodes = range(node_num)
+
+    for node in nodes:
+        g.add_node(node)
+
+    while 1:
+        head = random.choice(nodes)
+        tail = random.choice(nodes)
+
+        # loop defense
+        if head == tail and not self_loops:
+            continue
+
+        # multiple edge defense
+        if g.edge_by_node(head, tail) is not None and not multi_edges:
+            continue
+
+        # add the edge
+        g.add_edge(head, tail)
+        if g.number_of_edges() >= edge_num:
+            break
+
+    return g
+
+
+def generate_scale_free_graph(steps, growth_num, self_loops=False, multi_edges=False):
+    """
+    Generates and returns a :py:class:`~altgraph.Graph.Graph` instance that
+    will have *steps* \\* *growth_num* nodes and a scale free (powerlaw)
+    connectivity. Starting with a fully connected graph with *growth_num*
+    nodes at every step *growth_num* nodes are added to the graph and are
+    connected to existing nodes with a probability proportional to the degree
+    of these existing nodes.
+    """
+    # The code doesn't seem to do what the documentation claims.
+    graph = Graph.Graph()
+
+    # initialize the graph
+    store = []
+    for i in range(growth_num):
+        for j in range(i + 1, growth_num):
+            store.append(i)
+            store.append(j)
+            graph.add_edge(i, j)
+
+    # generate
+    for node in range(growth_num, steps * growth_num):
+        graph.add_node(node)
+        while graph.out_degree(node) < growth_num:
+            nbr = random.choice(store)
+
+            # loop defense
+            if node == nbr and not self_loops:
+                continue
+
+            # multi edge defense
+            if graph.edge_by_node(node, nbr) and not multi_edges:
+                continue
+
+            graph.add_edge(node, nbr)
+
+        for nbr in graph.out_nbrs(node):
+            store.append(node)
+            store.append(nbr)
+
+    return graph
+
+
+def filter_stack(graph, head, filters):
+    """
+    Perform a walk in a depth-first order starting
+    at *head*.
+
+    Returns (visited, removes, orphans).
+
+    * visited: the set of visited nodes
+    * removes: the list of nodes where the node
+      data does not all *filters*
+    * orphans: tuples of (last_good, node),
+      where node is not in removes, is directly
+      reachable from a node in *removes* and
+      *last_good* is the closest upstream node that is not
+      in *removes*.
+    """
+
+    visited, removes, orphans = {head}, set(), set()
+    stack = deque([(head, head)])
+    get_data = graph.node_data
+    get_edges = graph.out_edges
+    get_tail = graph.tail
+
+    while stack:
+        last_good, node = stack.pop()
+        data = get_data(node)
+        if data is not None:
+            for filtfunc in filters:
+                if not filtfunc(data):
+                    removes.add(node)
+                    break
+            else:
+                last_good = node
+        for edge in get_edges(node):
+            tail = get_tail(edge)
+            if last_good is not node:
+                orphans.add((last_good, tail))
+            if tail not in visited:
+                visited.add(tail)
+                stack.append((last_good, tail))
+
+    orphans = [(lg, tl) for (lg, tl) in orphans if tl not in removes]
+
+    return visited, removes, orphans

lib/spack/external/_vendoring/altgraph/LICENSE

@@ -0,0 +1,18 @@
+Copyright (c) 2004 Istvan Albert unless otherwise noted.
+Copyright (c) 2006-2010 Bob Ippolito
+Copyright (2) 2010-2020 Ronald Oussoren, et. al.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to
+deal in the Software without restriction, including without limitation the
+rights to use, copy, modify, merge, publish, distribute, sublicense,
+and/or sell copies of the Software, and to permit persons to whom the
+Software is furnished to do so.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+IN THE SOFTWARE.

lib/spack/external/_vendoring/altgraph/ObjectGraph.py

@@ -0,0 +1,212 @@
+"""
+altgraph.ObjectGraph - Graph of objects with an identifier
+==========================================================
+
+A graph of objects that have a "graphident" attribute.
+graphident is the key for the object in the graph
+"""
+
+from altgraph import GraphError
+from altgraph.Graph import Graph
+from altgraph.GraphUtil import filter_stack
+
+
+class ObjectGraph(object):
+    """
+    A graph of objects that have a "graphident" attribute.
+    graphident is the key for the object in the graph
+    """
+
+    def __init__(self, graph=None, debug=0):
+        if graph is None:
+            graph = Graph()
+        self.graphident = self
+        self.graph = graph
+        self.debug = debug
+        self.indent = 0
+        graph.add_node(self, None)
+
+    def __repr__(self):
+        return "<%s>" % (type(self).__name__,)
+
+    def flatten(self, condition=None, start=None):
+        """
+        Iterate over the subgraph that is entirely reachable by condition
+        starting from the given start node or the ObjectGraph root
+        """
+        if start is None:
+            start = self
+        start = self.getRawIdent(start)
+        return self.graph.iterdata(start=start, condition=condition)
+
+    def nodes(self):
+        for ident in self.graph:
+            node = self.graph.node_data(ident)
+            if node is not None:
+                yield self.graph.node_data(ident)
+
+    def get_edges(self, node):
+        if node is None:
+            node = self
+        start = self.getRawIdent(node)
+        _, _, outraw, incraw = self.graph.describe_node(start)
+
+        def iter_edges(lst, n):
+            seen = set()
+            for tpl in (self.graph.describe_edge(e) for e in lst):
+                ident = tpl[n]
+                if ident not in seen:
+                    yield self.findNode(ident)
+                    seen.add(ident)
+
+        return iter_edges(outraw, 3), iter_edges(incraw, 2)
+
+    def edgeData(self, fromNode, toNode):
+        if fromNode is None:
+            fromNode = self
+        start = self.getRawIdent(fromNode)
+        stop = self.getRawIdent(toNode)
+        edge = self.graph.edge_by_node(start, stop)
+        return self.graph.edge_data(edge)
+
+    def updateEdgeData(self, fromNode, toNode, edgeData):
+        if fromNode is None:
+            fromNode = self
+        start = self.getRawIdent(fromNode)
+        stop = self.getRawIdent(toNode)
+        edge = self.graph.edge_by_node(start, stop)
+        self.graph.update_edge_data(edge, edgeData)
+
+    def filterStack(self, filters):
+        """
+        Filter the ObjectGraph in-place by removing all edges to nodes that
+        do not match every filter in the given filter list
+
+        Returns a tuple containing the number of:
+            (nodes_visited, nodes_removed, nodes_orphaned)
+        """
+        visited, removes, orphans = filter_stack(self.graph, self, filters)
+
+        for last_good, tail in orphans:
+            self.graph.add_edge(last_good, tail, edge_data="orphan")
+
+        for node in removes:
+            self.graph.hide_node(node)
+
+        return len(visited) - 1, len(removes), len(orphans)
+
+    def removeNode(self, node):
+        """
+        Remove the given node from the graph if it exists
+        """
+        ident = self.getIdent(node)
+        if ident is not None:
+            self.graph.hide_node(ident)
+
+    def removeReference(self, fromnode, tonode):
+        """
+        Remove all edges from fromnode to tonode
+        """
+        if fromnode is None:
+            fromnode = self
+        fromident = self.getIdent(fromnode)
+        toident = self.getIdent(tonode)
+        if fromident is not None and toident is not None:
+            while True:
+                edge = self.graph.edge_by_node(fromident, toident)
+                if edge is None:
+                    break
+                self.graph.hide_edge(edge)
+
+    def getIdent(self, node):
+        """
+        Get the graph identifier for a node
+        """
+        ident = self.getRawIdent(node)
+        if ident is not None:
+            return ident
+        node = self.findNode(node)
+        if node is None:
+            return None
+        return node.graphident
+
+    def getRawIdent(self, node):
+        """
+        Get the identifier for a node object
+        """
+        if node is self:
+            return node
+        ident = getattr(node, "graphident", None)
+        return ident
+
+    def __contains__(self, node):
+        return self.findNode(node) is not None
+
+    def findNode(self, node):
+        """
+        Find the node on the graph
+        """
+        ident = self.getRawIdent(node)
+        if ident is None:
+            ident = node
+        try:
+            return self.graph.node_data(ident)
+        except KeyError:
+            return None
+
+    def addNode(self, node):
+        """
+        Add a node to the graph referenced by the root
+        """
+        self.msg(4, "addNode", node)
+
+        try:
+            self.graph.restore_node(node.graphident)
+        except GraphError:
+            self.graph.add_node(node.graphident, node)
+
+    def createReference(self, fromnode, tonode, edge_data=None):
+        """
+        Create a reference from fromnode to tonode
+        """
+        if fromnode is None:
+            fromnode = self
+        fromident, toident = self.getIdent(fromnode), self.getIdent(tonode)
+        if fromident is None or toident is None:
+            return
+        self.msg(4, "createReference", fromnode, tonode, edge_data)
+        self.graph.add_edge(fromident, toident, edge_data=edge_data)
+
+    def createNode(self, cls, name, *args, **kw):
+        """
+        Add a node of type cls to the graph if it does not already exist
+        by the given name
+        """
+        m = self.findNode(name)
+        if m is None:
+            m = cls(name, *args, **kw)
+            self.addNode(m)
+        return m
+
+    def msg(self, level, s, *args):
+        """
+        Print a debug message with the given level
+        """
+        if s and level <= self.debug:
+            print("%s%s %s" % ("  " * self.indent, s, " ".join(map(repr, args))))
+
+    def msgin(self, level, s, *args):
+        """
+        Print a debug message and indent
+        """
+        if level <= self.debug:
+            self.msg(level, s, *args)
+            self.indent = self.indent + 1
+
+    def msgout(self, level, s, *args):
+        """
+        Dedent and print a debug message
+        """
+        if level <= self.debug:
+            self.indent = self.indent - 1
+            self.msg(level, s, *args)

lib/spack/external/_vendoring/altgraph/__init__.py

@@ -0,0 +1,148 @@
+"""
+altgraph - a python graph library
+=================================
+
+altgraph is a fork of `graphlib <http://pygraphlib.sourceforge.net>`_ tailored
+to use newer Python 2.3+ features, including additional support used by the
+py2app suite (modulegraph and macholib, specifically).
+
+altgraph is a python based graph (network) representation and manipulation
+package.  It has started out as an extension to the
+`graph_lib module
+<http://www.ece.arizona.edu/~denny/python_nest/graph_lib_1.0.1.html>`_
+written by Nathan Denny it has been significantly optimized and expanded.
+
+The :class:`altgraph.Graph.Graph` class is loosely modeled after the
+`LEDA <http://www.algorithmic-solutions.com/enleda.htm>`_
+(Library of Efficient Datatypes) representation. The library
+includes methods for constructing graphs, BFS and DFS traversals,
+topological sort, finding connected components, shortest paths as well as a
+number graph statistics functions. The library can also visualize graphs
+via `graphviz <http://www.research.att.com/sw/tools/graphviz/>`_.
+
+The package contains the following modules:
+
+    -  the :py:mod:`altgraph.Graph` module contains the
+       :class:`~altgraph.Graph.Graph` class that stores the graph data
+
+    -  the :py:mod:`altgraph.GraphAlgo` module implements graph algorithms
+       operating on graphs (:py:class:`~altgraph.Graph.Graph`} instances)
+
+    -  the :py:mod:`altgraph.GraphStat` module contains functions for
+       computing statistical measures on graphs
+
+    -  the :py:mod:`altgraph.GraphUtil` module contains functions for
+       generating, reading and saving graphs
+
+    -  the :py:mod:`altgraph.Dot` module  contains functions for displaying
+       graphs via `graphviz <http://www.research.att.com/sw/tools/graphviz/>`_
+
+    -  the :py:mod:`altgraph.ObjectGraph` module implements a graph of
+       objects with a unique identifier
+
+Installation
+------------
+
+Download and unpack the archive then type::
+
+    python setup.py install
+
+This will install the library in the default location. For instructions on
+how to customize the install procedure read the output of::
+
+    python setup.py --help install
+
+To verify that the code works run the test suite::
+
+    python setup.py test
+
+Example usage
+-------------
+
+Lets assume that we want to analyze the graph below (links to the full picture)
+GRAPH_IMG.  Our script then might look the following way::
+
+    from altgraph import Graph, GraphAlgo, Dot
+
+    # these are the edges
+    edges = [ (1,2), (2,4), (1,3), (2,4), (3,4), (4,5), (6,5),
+        (6,14), (14,15), (6, 15),  (5,7), (7, 8), (7,13), (12,8),
+        (8,13), (11,12), (11,9), (13,11), (9,13), (13,10) ]
+
+    # creates the graph
+    graph = Graph.Graph()
+    for head, tail in edges:
+        graph.add_edge(head, tail)
+
+    # do a forward bfs from 1 at most to 20
+    print(graph.forw_bfs(1))
+
+This will print the nodes in some breadth first order::
+
+    [1, 2, 3, 4, 5, 7, 8, 13, 11, 10, 12, 9]
+
+If we wanted to get the hop-distance from node 1 to node 8
+we coud write::
+
+    print(graph.get_hops(1, 8))
+
+This will print the following::
+
+    [(1, 0), (2, 1), (3, 1), (4, 2), (5, 3), (7, 4), (8, 5)]
+
+Node 1 is at 0 hops since it is the starting node, nodes 2,3 are 1 hop away ...
+node 8 is 5 hops away. To find the shortest distance between two nodes you
+can use::
+
+    print(GraphAlgo.shortest_path(graph, 1, 12))
+
+It will print the nodes on one (if there are more) the shortest paths::
+
+    [1, 2, 4, 5, 7, 13, 11, 12]
+
+To display the graph we can use the GraphViz backend::
+
+    dot = Dot.Dot(graph)
+
+    # display the graph on the monitor
+    dot.display()
+
+    # save it in an image file
+    dot.save_img(file_name='graph', file_type='gif')
+
+
+
+..
+  @author: U{Istvan Albert<http://www.personal.psu.edu/staff/i/u/iua1/>}
+
+  @license:  MIT License
+
+  Copyright (c) 2004 Istvan Albert unless otherwise noted.
+
+  Permission is hereby granted, free of charge, to any person obtaining a copy
+  of this software and associated documentation files (the "Software"), to
+  deal in the Software without restriction, including without limitation the
+  rights to use, copy, modify, merge, publish, distribute, sublicense,
+  and/or sell copies of the Software, and to permit persons to whom the
+  Software is furnished to do so.
+
+  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+  IN THE SOFTWARE.
+  @requires: Python 2.3 or higher
+
+  @newfield contributor: Contributors:
+  @contributor: U{Reka Albert <http://www.phys.psu.edu/~ralbert/>}
+
+"""
+import pkg_resources
+
+__version__ = pkg_resources.require("altgraph")[0].version
+
+
+class GraphError(ValueError):
+    pass

lib/spack/external/_vendoring/attr/__init__.py

@@ -0,0 +1,79 @@
+# SPDX-License-Identifier: MIT
+
+
+import sys
+
+from functools import partial
+
+from . import converters, exceptions, filters, setters, validators
+from ._cmp import cmp_using
+from ._config import get_run_validators, set_run_validators
+from ._funcs import asdict, assoc, astuple, evolve, has, resolve_types
+from ._make import (
+    NOTHING,
+    Attribute,
+    Factory,
+    attrib,
+    attrs,
+    fields,
+    fields_dict,
+    make_class,
+    validate,
+)
+from ._version_info import VersionInfo
+
+
+__version__ = "22.1.0"
+__version_info__ = VersionInfo._from_version_string(__version__)
+
+__title__ = "attrs"
+__description__ = "Classes Without Boilerplate"
+__url__ = "https://www.attrs.org/"
+__uri__ = __url__
+__doc__ = __description__ + " <" + __uri__ + ">"
+
+__author__ = "Hynek Schlawack"
+__email__ = "hs@ox.cx"
+
+__license__ = "MIT"
+__copyright__ = "Copyright (c) 2015 Hynek Schlawack"
+
+
+s = attributes = attrs
+ib = attr = attrib
+dataclass = partial(attrs, auto_attribs=True)  # happy Easter ;)
+
+__all__ = [
+    "Attribute",
+    "Factory",
+    "NOTHING",
+    "asdict",
+    "assoc",
+    "astuple",
+    "attr",
+    "attrib",
+    "attributes",
+    "attrs",
+    "cmp_using",
+    "converters",
+    "evolve",
+    "exceptions",
+    "fields",
+    "fields_dict",
+    "filters",
+    "get_run_validators",
+    "has",
+    "ib",
+    "make_class",
+    "resolve_types",
+    "s",
+    "set_run_validators",
+    "setters",
+    "validate",
+    "validators",
+]
+
+if sys.version_info[:2] >= (3, 6):
+    from ._next_gen import define, field, frozen, mutable  # noqa: F401
+
+    __all__.extend(("define", "field", "frozen", "mutable"))

lib/spack/external/_vendoring/attr/__init__.pyi

@@ -0,0 +1,486 @@
+import sys
+
+from typing import (
+    Any,
+    Callable,
+    ClassVar,
+    Dict,
+    Generic,
+    List,
+    Mapping,
+    Optional,
+    Protocol,
+    Sequence,
+    Tuple,
+    Type,
+    TypeVar,
+    Union,
+    overload,
+)
+
+# `import X as X` is required to make these public
+from . import converters as converters
+from . import exceptions as exceptions
+from . import filters as filters
+from . import setters as setters
+from . import validators as validators
+from ._cmp import cmp_using as cmp_using
+from ._version_info import VersionInfo
+
+__version__: str
+__version_info__: VersionInfo
+__title__: str
+__description__: str
+__url__: str
+__uri__: str
+__author__: str
+__email__: str
+__license__: str
+__copyright__: str
+
+_T = TypeVar("_T")
+_C = TypeVar("_C", bound=type)
+
+_EqOrderType = Union[bool, Callable[[Any], Any]]
+_ValidatorType = Callable[[Any, Attribute[_T], _T], Any]
+_ConverterType = Callable[[Any], Any]
+_FilterType = Callable[[Attribute[_T], _T], bool]
+_ReprType = Callable[[Any], str]
+_ReprArgType = Union[bool, _ReprType]
+_OnSetAttrType = Callable[[Any, Attribute[Any], Any], Any]
+_OnSetAttrArgType = Union[
+    _OnSetAttrType, List[_OnSetAttrType], setters._NoOpType
+]
+_FieldTransformer = Callable[
+    [type, List[Attribute[Any]]], List[Attribute[Any]]
+]
+# FIXME: in reality, if multiple validators are passed they must be in a list
+# or tuple, but those are invariant and so would prevent subtypes of
+# _ValidatorType from working when passed in a list or tuple.
+_ValidatorArgType = Union[_ValidatorType[_T], Sequence[_ValidatorType[_T]]]
+
+# A protocol to be able to statically accept an attrs class.
+class AttrsInstance(Protocol):
+    __attrs_attrs__: ClassVar[Any]
+
+# _make --
+
+NOTHING: object
+
+# NOTE: Factory lies about its return type to make this possible:
+# `x: List[int] # = Factory(list)`
+# Work around mypy issue #4554 in the common case by using an overload.
+if sys.version_info >= (3, 8):
+    from typing import Literal
+    @overload
+    def Factory(factory: Callable[[], _T]) -> _T: ...
+    @overload
+    def Factory(
+        factory: Callable[[Any], _T],
+        takes_self: Literal[True],
+    ) -> _T: ...
+    @overload
+    def Factory(
+        factory: Callable[[], _T],
+        takes_self: Literal[False],
+    ) -> _T: ...
+
+else:
+    @overload
+    def Factory(factory: Callable[[], _T]) -> _T: ...
+    @overload
+    def Factory(
+        factory: Union[Callable[[Any], _T], Callable[[], _T]],
+        takes_self: bool = ...,
+    ) -> _T: ...
+
+# Static type inference support via __dataclass_transform__ implemented as per:
+# https://github.com/microsoft/pyright/blob/1.1.135/specs/dataclass_transforms.md
+# This annotation must be applied to all overloads of "define" and "attrs"
+#
+# NOTE: This is a typing construct and does not exist at runtime.  Extensions
+# wrapping attrs decorators should declare a separate __dataclass_transform__
+# signature in the extension module using the specification linked above to
+# provide pyright support.
+def __dataclass_transform__(
+    *,
+    eq_default: bool = True,
+    order_default: bool = False,
+    kw_only_default: bool = False,
+    field_descriptors: Tuple[Union[type, Callable[..., Any]], ...] = (()),
+) -> Callable[[_T], _T]: ...
+
+class Attribute(Generic[_T]):
+    name: str
+    default: Optional[_T]
+    validator: Optional[_ValidatorType[_T]]
+    repr: _ReprArgType
+    cmp: _EqOrderType
+    eq: _EqOrderType
+    order: _EqOrderType
+    hash: Optional[bool]
+    init: bool
+    converter: Optional[_ConverterType]
+    metadata: Dict[Any, Any]
+    type: Optional[Type[_T]]
+    kw_only: bool
+    on_setattr: _OnSetAttrType
+    def evolve(self, **changes: Any) -> "Attribute[Any]": ...
+
+# NOTE: We had several choices for the annotation to use for type arg:
+# 1) Type[_T]
+#   - Pros: Handles simple cases correctly
+#   - Cons: Might produce less informative errors in the case of conflicting
+#     TypeVars e.g. `attr.ib(default='bad', type=int)`
+# 2) Callable[..., _T]
+#   - Pros: Better error messages than #1 for conflicting TypeVars
+#   - Cons: Terrible error messages for validator checks.
+#   e.g. attr.ib(type=int, validator=validate_str)
+#        -> error: Cannot infer function type argument
+# 3) type (and do all of the work in the mypy plugin)
+#   - Pros: Simple here, and we could customize the plugin with our own errors.
+#   - Cons: Would need to write mypy plugin code to handle all the cases.
+# We chose option #1.
+
+# `attr` lies about its return type to make the following possible:
+#     attr()    -> Any
+#     attr(8)   -> int
+#     attr(validator=<some callable>)  -> Whatever the callable expects.
+# This makes this type of assignments possible:
+#     x: int = attr(8)
+#
+# This form catches explicit None or no default but with no other arguments
+# returns Any.
+@overload
+def attrib(
+    default: None = ...,
+    validator: None = ...,
+    repr: _ReprArgType = ...,
+    cmp: Optional[_EqOrderType] = ...,
+    hash: Optional[bool] = ...,
+    init: bool = ...,
+    metadata: Optional[Mapping[Any, Any]] = ...,
+    type: None = ...,
+    converter: None = ...,
+    factory: None = ...,
+    kw_only: bool = ...,
+    eq: Optional[_EqOrderType] = ...,
+    order: Optional[_EqOrderType] = ...,
+    on_setattr: Optional[_OnSetAttrArgType] = ...,
+) -> Any: ...
+
+# This form catches an explicit None or no default and infers the type from the
+# other arguments.
+@overload
+def attrib(
+    default: None = ...,
+    validator: Optional[_ValidatorArgType[_T]] = ...,
+    repr: _ReprArgType = ...,
+    cmp: Optional[_EqOrderType] = ...,
+    hash: Optional[bool] = ...,
+    init: bool = ...,
+    metadata: Optional[Mapping[Any, Any]] = ...,
+    type: Optional[Type[_T]] = ...,
+    converter: Optional[_ConverterType] = ...,
+    factory: Optional[Callable[[], _T]] = ...,
+    kw_only: bool = ...,
+    eq: Optional[_EqOrderType] = ...,
+    order: Optional[_EqOrderType] = ...,
+    on_setattr: Optional[_OnSetAttrArgType] = ...,
+) -> _T: ...
+
+# This form catches an explicit default argument.
+@overload
+def attrib(
+    default: _T,
+    validator: Optional[_ValidatorArgType[_T]] = ...,
+    repr: _ReprArgType = ...,
+    cmp: Optional[_EqOrderType] = ...,
+    hash: Optional[bool] = ...,
+    init: bool = ...,
+    metadata: Optional[Mapping[Any, Any]] = ...,
+    type: Optional[Type[_T]] = ...,
+    converter: Optional[_ConverterType] = ...,
+    factory: Optional[Callable[[], _T]] = ...,
+    kw_only: bool = ...,
+    eq: Optional[_EqOrderType] = ...,
+    order: Optional[_EqOrderType] = ...,
+    on_setattr: Optional[_OnSetAttrArgType] = ...,
+) -> _T: ...
+
+# This form covers type=non-Type: e.g. forward references (str), Any
+@overload
+def attrib(
+    default: Optional[_T] = ...,
+    validator: Optional[_ValidatorArgType[_T]] = ...,
+    repr: _ReprArgType = ...,
+    cmp: Optional[_EqOrderType] = ...,
+    hash: Optional[bool] = ...,
+    init: bool = ...,
+    metadata: Optional[Mapping[Any, Any]] = ...,
+    type: object = ...,
+    converter: Optional[_ConverterType] = ...,
+    factory: Optional[Callable[[], _T]] = ...,
+    kw_only: bool = ...,
+    eq: Optional[_EqOrderType] = ...,
+    order: Optional[_EqOrderType] = ...,
+    on_setattr: Optional[_OnSetAttrArgType] = ...,
+) -> Any: ...
+@overload
+def field(
+    *,
+    default: None = ...,
+    validator: None = ...,
+    repr: _ReprArgType = ...,
+    hash: Optional[bool] = ...,
+    init: bool = ...,
+    metadata: Optional[Mapping[Any, Any]] = ...,
+    converter: None = ...,
+    factory: None = ...,
+    kw_only: bool = ...,
+    eq: Optional[bool] = ...,
+    order: Optional[bool] = ...,
+    on_setattr: Optional[_OnSetAttrArgType] = ...,
+) -> Any: ...
+
+# This form catches an explicit None or no default and infers the type from the
+# other arguments.
+@overload
+def field(
+    *,
+    default: None = ...,
+    validator: Optional[_ValidatorArgType[_T]] = ...,
+    repr: _ReprArgType = ...,
+    hash: Optional[bool] = ...,
+    init: bool = ...,
+    metadata: Optional[Mapping[Any, Any]] = ...,
+    converter: Optional[_ConverterType] = ...,
+    factory: Optional[Callable[[], _T]] = ...,
+    kw_only: bool = ...,
+    eq: Optional[_EqOrderType] = ...,
+    order: Optional[_EqOrderType] = ...,
+    on_setattr: Optional[_OnSetAttrArgType] = ...,
+) -> _T: ...
+
+# This form catches an explicit default argument.
+@overload
+def field(
+    *,
+    default: _T,
+    validator: Optional[_ValidatorArgType[_T]] = ...,
+    repr: _ReprArgType = ...,
+    hash: Optional[bool] = ...,
+    init: bool = ...,
+    metadata: Optional[Mapping[Any, Any]] = ...,
+    converter: Optional[_ConverterType] = ...,
+    factory: Optional[Callable[[], _T]] = ...,
+    kw_only: bool = ...,
+    eq: Optional[_EqOrderType] = ...,
+    order: Optional[_EqOrderType] = ...,
+    on_setattr: Optional[_OnSetAttrArgType] = ...,
+) -> _T: ...
+
+# This form covers type=non-Type: e.g. forward references (str), Any
+@overload
+def field(
+    *,
+    default: Optional[_T] = ...,
+    validator: Optional[_ValidatorArgType[_T]] = ...,
+    repr: _ReprArgType = ...,
+    hash: Optional[bool] = ...,
+    init: bool = ...,
+    metadata: Optional[Mapping[Any, Any]] = ...,
+    converter: Optional[_ConverterType] = ...,
+    factory: Optional[Callable[[], _T]] = ...,
+    kw_only: bool = ...,
+    eq: Optional[_EqOrderType] = ...,
+    order: Optional[_EqOrderType] = ...,
+    on_setattr: Optional[_OnSetAttrArgType] = ...,
+) -> Any: ...
+@overload
+@__dataclass_transform__(order_default=True, field_descriptors=(attrib, field))
+def attrs(
+    maybe_cls: _C,
+    these: Optional[Dict[str, Any]] = ...,
+    repr_ns: Optional[str] = ...,
+    repr: bool = ...,
+    cmp: Optional[_EqOrderType] = ...,
+    hash: Optional[bool] = ...,
+    init: bool = ...,
+    slots: bool = ...,
+    frozen: bool = ...,
+    weakref_slot: bool = ...,
+    str: bool = ...,
+    auto_attribs: bool = ...,
+    kw_only: bool = ...,
+    cache_hash: bool = ...,
+    auto_exc: bool = ...,
+    eq: Optional[_EqOrderType] = ...,
+    order: Optional[_EqOrderType] = ...,
+    auto_detect: bool = ...,
+    collect_by_mro: bool = ...,
+    getstate_setstate: Optional[bool] = ...,
+    on_setattr: Optional[_OnSetAttrArgType] = ...,
+    field_transformer: Optional[_FieldTransformer] = ...,
+    match_args: bool = ...,
+) -> _C: ...
+@overload
+@__dataclass_transform__(order_default=True, field_descriptors=(attrib, field))
+def attrs(
+    maybe_cls: None = ...,
+    these: Optional[Dict[str, Any]] = ...,
+    repr_ns: Optional[str] = ...,
+    repr: bool = ...,
+    cmp: Optional[_EqOrderType] = ...,
+    hash: Optional[bool] = ...,
+    init: bool = ...,
+    slots: bool = ...,
+    frozen: bool = ...,
+    weakref_slot: bool = ...,
+    str: bool = ...,
+    auto_attribs: bool = ...,
+    kw_only: bool = ...,
+    cache_hash: bool = ...,
+    auto_exc: bool = ...,
+    eq: Optional[_EqOrderType] = ...,
+    order: Optional[_EqOrderType] = ...,
+    auto_detect: bool = ...,
+    collect_by_mro: bool = ...,
+    getstate_setstate: Optional[bool] = ...,
+    on_setattr: Optional[_OnSetAttrArgType] = ...,
+    field_transformer: Optional[_FieldTransformer] = ...,
+    match_args: bool = ...,
+) -> Callable[[_C], _C]: ...
+@overload
+@__dataclass_transform__(field_descriptors=(attrib, field))
+def define(
+    maybe_cls: _C,
+    *,
+    these: Optional[Dict[str, Any]] = ...,
+    repr: bool = ...,
+    hash: Optional[bool] = ...,
+    init: bool = ...,
+    slots: bool = ...,
+    frozen: bool = ...,
+    weakref_slot: bool = ...,
+    str: bool = ...,
+    auto_attribs: bool = ...,
+    kw_only: bool = ...,
+    cache_hash: bool = ...,
+    auto_exc: bool = ...,
+    eq: Optional[bool] = ...,
+    order: Optional[bool] = ...,
+    auto_detect: bool = ...,
+    getstate_setstate: Optional[bool] = ...,
+    on_setattr: Optional[_OnSetAttrArgType] = ...,
+    field_transformer: Optional[_FieldTransformer] = ...,
+    match_args: bool = ...,
+) -> _C: ...
+@overload
+@__dataclass_transform__(field_descriptors=(attrib, field))
+def define(
+    maybe_cls: None = ...,
+    *,
+    these: Optional[Dict[str, Any]] = ...,
+    repr: bool = ...,
+    hash: Optional[bool] = ...,
+    init: bool = ...,
+    slots: bool = ...,
+    frozen: bool = ...,
+    weakref_slot: bool = ...,
+    str: bool = ...,
+    auto_attribs: bool = ...,
+    kw_only: bool = ...,
+    cache_hash: bool = ...,
+    auto_exc: bool = ...,
+    eq: Optional[bool] = ...,
+    order: Optional[bool] = ...,
+    auto_detect: bool = ...,
+    getstate_setstate: Optional[bool] = ...,
+    on_setattr: Optional[_OnSetAttrArgType] = ...,
+    field_transformer: Optional[_FieldTransformer] = ...,
+    match_args: bool = ...,
+) -> Callable[[_C], _C]: ...
+
+mutable = define
+frozen = define  # they differ only in their defaults
+
+def fields(cls: Type[AttrsInstance]) -> Any: ...
+def fields_dict(cls: Type[AttrsInstance]) -> Dict[str, Attribute[Any]]: ...
+def validate(inst: AttrsInstance) -> None: ...
+def resolve_types(
+    cls: _C,
+    globalns: Optional[Dict[str, Any]] = ...,
+    localns: Optional[Dict[str, Any]] = ...,
+    attribs: Optional[List[Attribute[Any]]] = ...,
+) -> _C: ...
+
+# TODO: add support for returning a proper attrs class from the mypy plugin
+# we use Any instead of _CountingAttr so that e.g. `make_class('Foo',
+# [attr.ib()])` is valid
+def make_class(
+    name: str,
+    attrs: Union[List[str], Tuple[str, ...], Dict[str, Any]],
+    bases: Tuple[type, ...] = ...,
+    repr_ns: Optional[str] = ...,
+    repr: bool = ...,
+    cmp: Optional[_EqOrderType] = ...,
+    hash: Optional[bool] = ...,
+    init: bool = ...,
+    slots: bool = ...,
+    frozen: bool = ...,
+    weakref_slot: bool = ...,
+    str: bool = ...,
+    auto_attribs: bool = ...,
+    kw_only: bool = ...,
+    cache_hash: bool = ...,
+    auto_exc: bool = ...,
+    eq: Optional[_EqOrderType] = ...,
+    order: Optional[_EqOrderType] = ...,
+    collect_by_mro: bool = ...,
+    on_setattr: Optional[_OnSetAttrArgType] = ...,
+    field_transformer: Optional[_FieldTransformer] = ...,
+) -> type: ...
+
+# _funcs --
+
+# TODO: add support for returning TypedDict from the mypy plugin
+# FIXME: asdict/astuple do not honor their factory args. Waiting on one of
+# these:
+# https://github.com/python/mypy/issues/4236
+# https://github.com/python/typing/issues/253
+# XXX: remember to fix attrs.asdict/astuple too!
+def asdict(
+    inst: AttrsInstance,
+    recurse: bool = ...,
+    filter: Optional[_FilterType[Any]] = ...,
+    dict_factory: Type[Mapping[Any, Any]] = ...,
+    retain_collection_types: bool = ...,
+    value_serializer: Optional[
+        Callable[[type, Attribute[Any], Any], Any]
+    ] = ...,
+    tuple_keys: Optional[bool] = ...,
+) -> Dict[str, Any]: ...
+
+# TODO: add support for returning NamedTuple from the mypy plugin
+def astuple(
+    inst: AttrsInstance,
+    recurse: bool = ...,
+    filter: Optional[_FilterType[Any]] = ...,
+    tuple_factory: Type[Sequence[Any]] = ...,
+    retain_collection_types: bool = ...,
+) -> Tuple[Any, ...]: ...
+def has(cls: type) -> bool: ...
+def assoc(inst: _T, **changes: Any) -> _T: ...
+def evolve(inst: _T, **changes: Any) -> _T: ...
+
+# _config --
+
+def set_run_validators(run: bool) -> None: ...
+def get_run_validators() -> bool: ...
+
+# aliases --
+
+s = attributes = attrs
+ib = attr = attrib
+dataclass = attrs  # Technically, partial(attrs, auto_attribs=True) ;)

lib/spack/external/_vendoring/attr/_cmp.py

@@ -0,0 +1,155 @@
+# SPDX-License-Identifier: MIT
+
+
+import functools
+import types
+
+from ._make import _make_ne
+
+
+_operation_names = {"eq": "==", "lt": "<", "le": "<=", "gt": ">", "ge": ">="}
+
+
+def cmp_using(
+    eq=None,
+    lt=None,
+    le=None,
+    gt=None,
+    ge=None,
+    require_same_type=True,
+    class_name="Comparable",
+):
+    """
+    Create a class that can be passed into `attr.ib`'s ``eq``, ``order``, and
+    ``cmp`` arguments to customize field comparison.
+
+    The resulting class will have a full set of ordering methods if
+    at least one of ``{lt, le, gt, ge}`` and ``eq``  are provided.
+
+    :param Optional[callable] eq: `callable` used to evaluate equality
+        of two objects.
+    :param Optional[callable] lt: `callable` used to evaluate whether
+        one object is less than another object.
+    :param Optional[callable] le: `callable` used to evaluate whether
+        one object is less than or equal to another object.
+    :param Optional[callable] gt: `callable` used to evaluate whether
+        one object is greater than another object.
+    :param Optional[callable] ge: `callable` used to evaluate whether
+        one object is greater than or equal to another object.
+
+    :param bool require_same_type: When `True`, equality and ordering methods
+        will return `NotImplemented` if objects are not of the same type.
+
+    :param Optional[str] class_name: Name of class. Defaults to 'Comparable'.
+
+    See `comparison` for more details.
+
+    .. versionadded:: 21.1.0
+    """
+
+    body = {
+        "__slots__": ["value"],
+        "__init__": _make_init(),
+        "_requirements": [],
+        "_is_comparable_to": _is_comparable_to,
+    }
+
+    # Add operations.
+    num_order_functions = 0
+    has_eq_function = False
+
+    if eq is not None:
+        has_eq_function = True
+        body["__eq__"] = _make_operator("eq", eq)
+        body["__ne__"] = _make_ne()
+
+    if lt is not None:
+        num_order_functions += 1
+        body["__lt__"] = _make_operator("lt", lt)
+
+    if le is not None:
+        num_order_functions += 1
+        body["__le__"] = _make_operator("le", le)
+
+    if gt is not None:
+        num_order_functions += 1
+        body["__gt__"] = _make_operator("gt", gt)
+
+    if ge is not None:
+        num_order_functions += 1
+        body["__ge__"] = _make_operator("ge", ge)
+
+    type_ = types.new_class(
+        class_name, (object,), {}, lambda ns: ns.update(body)
+    )
+
+    # Add same type requirement.
+    if require_same_type:
+        type_._requirements.append(_check_same_type)
+
+    # Add total ordering if at least one operation was defined.
+    if 0 < num_order_functions < 4:
+        if not has_eq_function:
+            # functools.total_ordering requires __eq__ to be defined,
+            # so raise early error here to keep a nice stack.
+            raise ValueError(
+                "eq must be define is order to complete ordering from "
+                "lt, le, gt, ge."
+            )
+        type_ = functools.total_ordering(type_)
+
+    return type_
+
+
+def _make_init():
+    """
+    Create __init__ method.
+    """
+
+    def __init__(self, value):
+        """
+        Initialize object with *value*.
+        """
+        self.value = value
+
+    return __init__
+
+
+def _make_operator(name, func):
+    """
+    Create operator method.
+    """
+
+    def method(self, other):
+        if not self._is_comparable_to(other):
+            return NotImplemented
+
+        result = func(self.value, other.value)
+        if result is NotImplemented:
+            return NotImplemented
+
+        return result
+
+    method.__name__ = "__%s__" % (name,)
+    method.__doc__ = "Return a %s b.  Computed by attrs." % (
+        _operation_names[name],
+    )
+
+    return method
+
+
+def _is_comparable_to(self, other):
+    """
+    Check whether `other` is comparable to `self`.
+    """
+    for func in self._requirements:
+        if not func(self, other):
+            return False
+    return True
+
+
+def _check_same_type(self, other):
+    """
+    Return True if *self* and *other* are of the same type, False otherwise.
+    """
+    return other.value.__class__ is self.value.__class__

lib/spack/external/_vendoring/attr/_cmp.pyi

@@ -0,0 +1,13 @@
+from typing import Any, Callable, Optional, Type
+
+_CompareWithType = Callable[[Any, Any], bool]
+
+def cmp_using(
+    eq: Optional[_CompareWithType],
+    lt: Optional[_CompareWithType],
+    le: Optional[_CompareWithType],
+    gt: Optional[_CompareWithType],
+    ge: Optional[_CompareWithType],
+    require_same_type: bool,
+    class_name: str,
+) -> Type: ...

lib/spack/external/_vendoring/attr/_compat.py

@@ -0,0 +1,185 @@
+# SPDX-License-Identifier: MIT
+
+
+import inspect
+import platform
+import sys
+import threading
+import types
+import warnings
+
+from collections.abc import Mapping, Sequence  # noqa
+
+
+PYPY = platform.python_implementation() == "PyPy"
+PY36 = sys.version_info[:2] >= (3, 6)
+HAS_F_STRINGS = PY36
+PY310 = sys.version_info[:2] >= (3, 10)
+
+
+if PYPY or PY36:
+    ordered_dict = dict
+else:
+    from collections import OrderedDict
+
+    ordered_dict = OrderedDict
+
+
+def just_warn(*args, **kw):
+    warnings.warn(
+        "Running interpreter doesn't sufficiently support code object "
+        "introspection.  Some features like bare super() or accessing "
+        "__class__ will not work with slotted classes.",
+        RuntimeWarning,
+        stacklevel=2,
+    )
+
+
+class _AnnotationExtractor:
+    """
+    Extract type annotations from a callable, returning None whenever there
+    is none.
+    """
+
+    __slots__ = ["sig"]
+
+    def __init__(self, callable):
+        try:
+            self.sig = inspect.signature(callable)
+        except (ValueError, TypeError):  # inspect failed
+            self.sig = None
+
+    def get_first_param_type(self):
+        """
+        Return the type annotation of the first argument if it's not empty.
+        """
+        if not self.sig:
+            return None
+
+        params = list(self.sig.parameters.values())
+        if params and params[0].annotation is not inspect.Parameter.empty:
+            return params[0].annotation
+
+        return None
+
+    def get_return_type(self):
+        """
+        Return the return type if it's not empty.
+        """
+        if (
+            self.sig
+            and self.sig.return_annotation is not inspect.Signature.empty
+        ):
+            return self.sig.return_annotation
+
+        return None
+
+
+def make_set_closure_cell():
+    """Return a function of two arguments (cell, value) which sets
+    the value stored in the closure cell `cell` to `value`.
+    """
+    # pypy makes this easy. (It also supports the logic below, but
+    # why not do the easy/fast thing?)
+    if PYPY:
+
+        def set_closure_cell(cell, value):
+            cell.__setstate__((value,))
+
+        return set_closure_cell
+
+    # Otherwise gotta do it the hard way.
+
+    # Create a function that will set its first cellvar to `value`.
+    def set_first_cellvar_to(value):
+        x = value
+        return
+
+        # This function will be eliminated as dead code, but
+        # not before its reference to `x` forces `x` to be
+        # represented as a closure cell rather than a local.
+        def force_x_to_be_a_cell():  # pragma: no cover
+            return x
+
+    try:
+        # Extract the code object and make sure our assumptions about
+        # the closure behavior are correct.
+        co = set_first_cellvar_to.__code__
+        if co.co_cellvars != ("x",) or co.co_freevars != ():
+            raise AssertionError  # pragma: no cover
+
+        # Convert this code object to a code object that sets the
+        # function's first _freevar_ (not cellvar) to the argument.
+        if sys.version_info >= (3, 8):
+
+            def set_closure_cell(cell, value):
+                cell.cell_contents = value
+
+        else:
+            args = [co.co_argcount]
+            args.append(co.co_kwonlyargcount)
+            args.extend(
+                [
+                    co.co_nlocals,
+                    co.co_stacksize,
+                    co.co_flags,
+                    co.co_code,
+                    co.co_consts,
+                    co.co_names,
+                    co.co_varnames,
+                    co.co_filename,
+                    co.co_name,
+                    co.co_firstlineno,
+                    co.co_lnotab,
+                    # These two arguments are reversed:
+                    co.co_cellvars,
+                    co.co_freevars,
+                ]
+            )
+            set_first_freevar_code = types.CodeType(*args)
+
+            def set_closure_cell(cell, value):
+                # Create a function using the set_first_freevar_code,
+                # whose first closure cell is `cell`. Calling it will
+                # change the value of that cell.
+                setter = types.FunctionType(
+                    set_first_freevar_code, {}, "setter", (), (cell,)
+                )
+                # And call it to set the cell.
+                setter(value)
+
+        # Make sure it works on this interpreter:
+        def make_func_with_cell():
+            x = None
+
+            def func():
+                return x  # pragma: no cover
+
+            return func
+
+        cell = make_func_with_cell().__closure__[0]
+        set_closure_cell(cell, 100)
+        if cell.cell_contents != 100:
+            raise AssertionError  # pragma: no cover
+
+    except Exception:
+        return just_warn
+    else:
+        return set_closure_cell
+
+
+set_closure_cell = make_set_closure_cell()
+
+# Thread-local global to track attrs instances which are already being repr'd.
+# This is needed because there is no other (thread-safe) way to pass info
+# about the instances that are already being repr'd through the call stack
+# in order to ensure we don't perform infinite recursion.
+#
+# For instance, if an instance contains a dict which contains that instance,
+# we need to know that we're already repr'ing the outside instance from within
+# the dict's repr() call.
+#
+# This lives here rather than in _make.py so that the functions in _make.py
+# don't have a direct reference to the thread-local in their globals dict.
+# If they have such a reference, it breaks cloudpickle.
+repr_context = threading.local()

lib/spack/external/_vendoring/attr/_config.py

@@ -0,0 +1,31 @@
+# SPDX-License-Identifier: MIT
+
+
+__all__ = ["set_run_validators", "get_run_validators"]
+
+_run_validators = True
+
+
+def set_run_validators(run):
+    """
+    Set whether or not validators are run.  By default, they are run.
+
+    .. deprecated:: 21.3.0 It will not be removed, but it also will not be
+        moved to new ``attrs`` namespace. Use `attrs.validators.set_disabled()`
+        instead.
+    """
+    if not isinstance(run, bool):
+        raise TypeError("'run' must be bool.")
+    global _run_validators
+    _run_validators = run
+
+
+def get_run_validators():
+    """
+    Return whether or not validators are run.
+
+    .. deprecated:: 21.3.0 It will not be removed, but it also will not be
+        moved to new ``attrs`` namespace. Use `attrs.validators.get_disabled()`
+        instead.
+    """
+    return _run_validators

lib/spack/external/_vendoring/attr/_funcs.py

@@ -0,0 +1,420 @@
+# SPDX-License-Identifier: MIT
+
+
+import copy
+
+from ._make import NOTHING, _obj_setattr, fields
+from .exceptions import AttrsAttributeNotFoundError
+
+
+def asdict(
+    inst,
+    recurse=True,
+    filter=None,
+    dict_factory=dict,
+    retain_collection_types=False,
+    value_serializer=None,
+):
+    """
+    Return the ``attrs`` attribute values of *inst* as a dict.
+
+    Optionally recurse into other ``attrs``-decorated classes.
+
+    :param inst: Instance of an ``attrs``-decorated class.
+    :param bool recurse: Recurse into classes that are also
+        ``attrs``-decorated.
+    :param callable filter: A callable whose return code determines whether an
+        attribute or element is included (``True``) or dropped (``False``).  Is
+        called with the `attrs.Attribute` as the first argument and the
+        value as the second argument.
+    :param callable dict_factory: A callable to produce dictionaries from.  For
+        example, to produce ordered dictionaries instead of normal Python
+        dictionaries, pass in ``collections.OrderedDict``.
+    :param bool retain_collection_types: Do not convert to ``list`` when
+        encountering an attribute whose type is ``tuple`` or ``set``.  Only
+        meaningful if ``recurse`` is ``True``.
+    :param Optional[callable] value_serializer: A hook that is called for every
+        attribute or dict key/value.  It receives the current instance, field
+        and value and must return the (updated) value.  The hook is run *after*
+        the optional *filter* has been applied.
+
+    :rtype: return type of *dict_factory*
+
+    :raise attr.exceptions.NotAnAttrsClassError: If *cls* is not an ``attrs``
+        class.
+
+    ..  versionadded:: 16.0.0 *dict_factory*
+    ..  versionadded:: 16.1.0 *retain_collection_types*
+    ..  versionadded:: 20.3.0 *value_serializer*
+    ..  versionadded:: 21.3.0 If a dict has a collection for a key, it is
+        serialized as a tuple.
+    """
+    attrs = fields(inst.__class__)
+    rv = dict_factory()
+    for a in attrs:
+        v = getattr(inst, a.name)
+        if filter is not None and not filter(a, v):
+            continue
+
+        if value_serializer is not None:
+            v = value_serializer(inst, a, v)
+
+        if recurse is True:
+            if has(v.__class__):
+                rv[a.name] = asdict(
+                    v,
+                    recurse=True,
+                    filter=filter,
+                    dict_factory=dict_factory,
+                    retain_collection_types=retain_collection_types,
+                    value_serializer=value_serializer,
+                )
+            elif isinstance(v, (tuple, list, set, frozenset)):
+                cf = v.__class__ if retain_collection_types is True else list
+                rv[a.name] = cf(
+                    [
+                        _asdict_anything(
+                            i,
+                            is_key=False,
+                            filter=filter,
+                            dict_factory=dict_factory,
+                            retain_collection_types=retain_collection_types,
+                            value_serializer=value_serializer,
+                        )
+                        for i in v
+                    ]
+                )
+            elif isinstance(v, dict):
+                df = dict_factory
+                rv[a.name] = df(
+                    (
+                        _asdict_anything(
+                            kk,
+                            is_key=True,
+                            filter=filter,
+                            dict_factory=df,
+                            retain_collection_types=retain_collection_types,
+                            value_serializer=value_serializer,
+                        ),
+                        _asdict_anything(
+                            vv,
+                            is_key=False,
+                            filter=filter,
+                            dict_factory=df,
+                            retain_collection_types=retain_collection_types,
+                            value_serializer=value_serializer,
+                        ),
+                    )
+                    for kk, vv in v.items()
+                )
+            else:
+                rv[a.name] = v
+        else:
+            rv[a.name] = v
+    return rv
+
+
+def _asdict_anything(
+    val,
+    is_key,
+    filter,
+    dict_factory,
+    retain_collection_types,
+    value_serializer,
+):
+    """
+    ``asdict`` only works on attrs instances, this works on anything.
+    """
+    if getattr(val.__class__, "__attrs_attrs__", None) is not None:
+        # Attrs class.
+        rv = asdict(
+            val,
+            recurse=True,
+            filter=filter,
+            dict_factory=dict_factory,
+            retain_collection_types=retain_collection_types,
+            value_serializer=value_serializer,
+        )
+    elif isinstance(val, (tuple, list, set, frozenset)):
+        if retain_collection_types is True:
+            cf = val.__class__
+        elif is_key:
+            cf = tuple
+        else:
+            cf = list
+
+        rv = cf(
+            [
+                _asdict_anything(
+                    i,
+                    is_key=False,
+                    filter=filter,
+                    dict_factory=dict_factory,
+                    retain_collection_types=retain_collection_types,
+                    value_serializer=value_serializer,
+                )
+                for i in val
+            ]
+        )
+    elif isinstance(val, dict):
+        df = dict_factory
+        rv = df(
+            (
+                _asdict_anything(
+                    kk,
+                    is_key=True,
+                    filter=filter,
+                    dict_factory=df,
+                    retain_collection_types=retain_collection_types,
+                    value_serializer=value_serializer,
+                ),
+                _asdict_anything(
+                    vv,
+                    is_key=False,
+                    filter=filter,
+                    dict_factory=df,
+                    retain_collection_types=retain_collection_types,
+                    value_serializer=value_serializer,
+                ),
+            )
+            for kk, vv in val.items()
+        )
+    else:
+        rv = val
+        if value_serializer is not None:
+            rv = value_serializer(None, None, rv)
+
+    return rv
+
+
+def astuple(
+    inst,
+    recurse=True,
+    filter=None,
+    tuple_factory=tuple,
+    retain_collection_types=False,
+):
+    """
+    Return the ``attrs`` attribute values of *inst* as a tuple.
+
+    Optionally recurse into other ``attrs``-decorated classes.
+
+    :param inst: Instance of an ``attrs``-decorated class.
+    :param bool recurse: Recurse into classes that are also
+        ``attrs``-decorated.
+    :param callable filter: A callable whose return code determines whether an
+        attribute or element is included (``True``) or dropped (``False``).  Is
+        called with the `attrs.Attribute` as the first argument and the
+        value as the second argument.
+    :param callable tuple_factory: A callable to produce tuples from.  For
+        example, to produce lists instead of tuples.
+    :param bool retain_collection_types: Do not convert to ``list``
+        or ``dict`` when encountering an attribute which type is
+        ``tuple``, ``dict`` or ``set``.  Only meaningful if ``recurse`` is
+        ``True``.
+
+    :rtype: return type of *tuple_factory*
+
+    :raise attr.exceptions.NotAnAttrsClassError: If *cls* is not an ``attrs``
+        class.
+
+    ..  versionadded:: 16.2.0
+    """
+    attrs = fields(inst.__class__)
+    rv = []
+    retain = retain_collection_types  # Very long. :/
+    for a in attrs:
+        v = getattr(inst, a.name)
+        if filter is not None and not filter(a, v):
+            continue
+        if recurse is True:
+            if has(v.__class__):
+                rv.append(
+                    astuple(
+                        v,
+                        recurse=True,
+                        filter=filter,
+                        tuple_factory=tuple_factory,
+                        retain_collection_types=retain,
+                    )
+                )
+            elif isinstance(v, (tuple, list, set, frozenset)):
+                cf = v.__class__ if retain is True else list
+                rv.append(
+                    cf(
+                        [
+                            astuple(
+                                j,
+                                recurse=True,
+                                filter=filter,
+                                tuple_factory=tuple_factory,
+                                retain_collection_types=retain,
+                            )
+                            if has(j.__class__)
+                            else j
+                            for j in v
+                        ]
+                    )
+                )
+            elif isinstance(v, dict):
+                df = v.__class__ if retain is True else dict
+                rv.append(
+                    df(
+                        (
+                            astuple(
+                                kk,
+                                tuple_factory=tuple_factory,
+                                retain_collection_types=retain,
+                            )
+                            if has(kk.__class__)
+                            else kk,
+                            astuple(
+                                vv,
+                                tuple_factory=tuple_factory,
+                                retain_collection_types=retain,
+                            )
+                            if has(vv.__class__)
+                            else vv,
+                        )
+                        for kk, vv in v.items()
+                    )
+                )
+            else:
+                rv.append(v)
+        else:
+            rv.append(v)
+
+    return rv if tuple_factory is list else tuple_factory(rv)
+
+
+def has(cls):
+    """
+    Check whether *cls* is a class with ``attrs`` attributes.
+
+    :param type cls: Class to introspect.
+    :raise TypeError: If *cls* is not a class.
+
+    :rtype: bool
+    """
+    return getattr(cls, "__attrs_attrs__", None) is not None
+
+
+def assoc(inst, **changes):
+    """
+    Copy *inst* and apply *changes*.
+
+    :param inst: Instance of a class with ``attrs`` attributes.
+    :param changes: Keyword changes in the new copy.
+
+    :return: A copy of inst with *changes* incorporated.
+
+    :raise attr.exceptions.AttrsAttributeNotFoundError: If *attr_name* couldn't
+        be found on *cls*.
+    :raise attr.exceptions.NotAnAttrsClassError: If *cls* is not an ``attrs``
+        class.
+
+    ..  deprecated:: 17.1.0
+        Use `attrs.evolve` instead if you can.
+        This function will not be removed du to the slightly different approach
+        compared to `attrs.evolve`.
+    """
+    import warnings
+
+    warnings.warn(
+        "assoc is deprecated and will be removed after 2018/01.",
+        DeprecationWarning,
+        stacklevel=2,
+    )
+    new = copy.copy(inst)
+    attrs = fields(inst.__class__)
+    for k, v in changes.items():
+        a = getattr(attrs, k, NOTHING)
+        if a is NOTHING:
+            raise AttrsAttributeNotFoundError(
+                "{k} is not an attrs attribute on {cl}.".format(
+                    k=k, cl=new.__class__
+                )
+            )
+        _obj_setattr(new, k, v)
+    return new
+
+
+def evolve(inst, **changes):
+    """
+    Create a new instance, based on *inst* with *changes* applied.
+
+    :param inst: Instance of a class with ``attrs`` attributes.
+    :param changes: Keyword changes in the new copy.
+
+    :return: A copy of inst with *changes* incorporated.
+
+    :raise TypeError: If *attr_name* couldn't be found in the class
+        ``__init__``.
+    :raise attr.exceptions.NotAnAttrsClassError: If *cls* is not an ``attrs``
+        class.
+
+    ..  versionadded:: 17.1.0
+    """
+    cls = inst.__class__
+    attrs = fields(cls)
+    for a in attrs:
+        if not a.init:
+            continue
+        attr_name = a.name  # To deal with private attributes.
+        init_name = attr_name if attr_name[0] != "_" else attr_name[1:]
+        if init_name not in changes:
+            changes[init_name] = getattr(inst, attr_name)
+
+    return cls(**changes)
+
+
+def resolve_types(cls, globalns=None, localns=None, attribs=None):
+    """
+    Resolve any strings and forward annotations in type annotations.
+
+    This is only required if you need concrete types in `Attribute`'s *type*
+    field. In other words, you don't need to resolve your types if you only
+    use them for static type checking.
+
+    With no arguments, names will be looked up in the module in which the class
+    was created. If this is not what you want, e.g. if the name only exists
+    inside a method, you may pass *globalns* or *localns* to specify other
+    dictionaries in which to look up these names. See the docs of
+    `typing.get_type_hints` for more details.
+
+    :param type cls: Class to resolve.
+    :param Optional[dict] globalns: Dictionary containing global variables.
+    :param Optional[dict] localns: Dictionary containing local variables.
+    :param Optional[list] attribs: List of attribs for the given class.
+        This is necessary when calling from inside a ``field_transformer``
+        since *cls* is not an ``attrs`` class yet.
+
+    :raise TypeError: If *cls* is not a class.
+    :raise attr.exceptions.NotAnAttrsClassError: If *cls* is not an ``attrs``
+        class and you didn't pass any attribs.
+    :raise NameError: If types cannot be resolved because of missing variables.
+
+    :returns: *cls* so you can use this function also as a class decorator.
+        Please note that you have to apply it **after** `attrs.define`. That
+        means the decorator has to come in the line **before** `attrs.define`.
+
+    ..  versionadded:: 20.1.0
+    ..  versionadded:: 21.1.0 *attribs*
+
+    """
+    # Since calling get_type_hints is expensive we cache whether we've
+    # done it already.
+    if getattr(cls, "__attrs_types_resolved__", None) != cls:
+        import typing
+
+        hints = typing.get_type_hints(cls, globalns=globalns, localns=localns)
+        for field in fields(cls) if attribs is None else attribs:
+            if field.name in hints:
+                # Since fields have been frozen we must work around it.
+                _obj_setattr(field, "type", hints[field.name])
+        # We store the class we resolved so that subclasses know they haven't
+        # been resolved.
+        cls.__attrs_types_resolved__ = cls
+
+    # Return the class so you can use it as a decorator too.
+    return cls

lib/spack/external/_vendoring/attr/_next_gen.py

@@ -0,0 +1,220 @@
+# SPDX-License-Identifier: MIT
+
+"""
+These are Python 3.6+-only and keyword-only APIs that call `attr.s` and
+`attr.ib` with different default values.
+"""
+
+
+from functools import partial
+
+from . import setters
+from ._funcs import asdict as _asdict
+from ._funcs import astuple as _astuple
+from ._make import (
+    NOTHING,
+    _frozen_setattrs,
+    _ng_default_on_setattr,
+    attrib,
+    attrs,
+)
+from .exceptions import UnannotatedAttributeError
+
+
+def define(
+    maybe_cls=None,
+    *,
+    these=None,
+    repr=None,
+    hash=None,
+    init=None,
+    slots=True,
+    frozen=False,
+    weakref_slot=True,
+    str=False,
+    auto_attribs=None,
+    kw_only=False,
+    cache_hash=False,
+    auto_exc=True,
+    eq=None,
+    order=False,
+    auto_detect=True,
+    getstate_setstate=None,
+    on_setattr=None,
+    field_transformer=None,
+    match_args=True,
+):
+    r"""
+    Define an ``attrs`` class.
+
+    Differences to the classic `attr.s` that it uses underneath:
+
+    - Automatically detect whether or not *auto_attribs* should be `True` (c.f.
+      *auto_attribs* parameter).
+    - If *frozen* is `False`, run converters and validators when setting an
+      attribute by default.
+    - *slots=True*
+
+      .. caution::
+
+         Usually this has only upsides and few visible effects in everyday
+         programming. But it *can* lead to some suprising behaviors, so please
+         make sure to read :term:`slotted classes`.
+    - *auto_exc=True*
+    - *auto_detect=True*
+    - *order=False*
+    - Some options that were only relevant on Python 2 or were kept around for
+      backwards-compatibility have been removed.
+
+    Please note that these are all defaults and you can change them as you
+    wish.
+
+    :param Optional[bool] auto_attribs: If set to `True` or `False`, it behaves
+       exactly like `attr.s`. If left `None`, `attr.s` will try to guess:
+
+       1. If any attributes are annotated and no unannotated `attrs.fields`\ s
+          are found, it assumes *auto_attribs=True*.
+       2. Otherwise it assumes *auto_attribs=False* and tries to collect
+          `attrs.fields`\ s.
+
+    For now, please refer to `attr.s` for the rest of the parameters.
+
+    .. versionadded:: 20.1.0
+    .. versionchanged:: 21.3.0 Converters are also run ``on_setattr``.
+    """
+
+    def do_it(cls, auto_attribs):
+        return attrs(
+            maybe_cls=cls,
+            these=these,
+            repr=repr,
+            hash=hash,
+            init=init,
+            slots=slots,
+            frozen=frozen,
+            weakref_slot=weakref_slot,
+            str=str,
+            auto_attribs=auto_attribs,
+            kw_only=kw_only,
+            cache_hash=cache_hash,
+            auto_exc=auto_exc,
+            eq=eq,
+            order=order,
+            auto_detect=auto_detect,
+            collect_by_mro=True,
+            getstate_setstate=getstate_setstate,
+            on_setattr=on_setattr,
+            field_transformer=field_transformer,
+            match_args=match_args,
+        )
+
+    def wrap(cls):
+        """
+        Making this a wrapper ensures this code runs during class creation.
+
+        We also ensure that frozen-ness of classes is inherited.
+        """
+        nonlocal frozen, on_setattr
+
+        had_on_setattr = on_setattr not in (None, setters.NO_OP)
+
+        # By default, mutable classes convert & validate on setattr.
+        if frozen is False and on_setattr is None:
+            on_setattr = _ng_default_on_setattr
+
+        # However, if we subclass a frozen class, we inherit the immutability
+        # and disable on_setattr.
+        for base_cls in cls.__bases__:
+            if base_cls.__setattr__ is _frozen_setattrs:
+                if had_on_setattr:
+                    raise ValueError(
+                        "Frozen classes can't use on_setattr "
+                        "(frozen-ness was inherited)."
+                    )
+
+                on_setattr = setters.NO_OP
+                break
+
+        if auto_attribs is not None:
+            return do_it(cls, auto_attribs)
+
+        try:
+            return do_it(cls, True)
+        except UnannotatedAttributeError:
+            return do_it(cls, False)
+
+    # maybe_cls's type depends on the usage of the decorator.  It's a class
+    # if it's used as `@attrs` but ``None`` if used as `@attrs()`.
+    if maybe_cls is None:
+        return wrap
+    else:
+        return wrap(maybe_cls)
+
+
+mutable = define
+frozen = partial(define, frozen=True, on_setattr=None)
+
+
+def field(
+    *,
+    default=NOTHING,
+    validator=None,
+    repr=True,
+    hash=None,
+    init=True,
+    metadata=None,
+    converter=None,
+    factory=None,
+    kw_only=False,
+    eq=None,
+    order=None,
+    on_setattr=None,
+):
+    """
+    Identical to `attr.ib`, except keyword-only and with some arguments
+    removed.
+
+    .. versionadded:: 20.1.0
+    """
+    return attrib(
+        default=default,
+        validator=validator,
+        repr=repr,
+        hash=hash,
+        init=init,
+        metadata=metadata,
+        converter=converter,
+        factory=factory,
+        kw_only=kw_only,
+        eq=eq,
+        order=order,
+        on_setattr=on_setattr,
+    )
+
+
+def asdict(inst, *, recurse=True, filter=None, value_serializer=None):
+    """
+    Same as `attr.asdict`, except that collections types are always retained
+    and dict is always used as *dict_factory*.
+
+    .. versionadded:: 21.3.0
+    """
+    return _asdict(
+        inst=inst,
+        recurse=recurse,
+        filter=filter,
+        value_serializer=value_serializer,
+        retain_collection_types=True,
+    )
+
+
+def astuple(inst, *, recurse=True, filter=None):
+    """
+    Same as `attr.astuple`, except that collections types are always retained
+    and `tuple` is always used as the *tuple_factory*.
+
+    .. versionadded:: 21.3.0
+    """
+    return _astuple(
+        inst=inst, recurse=recurse, filter=filter, retain_collection_types=True
+    )

lib/spack/external/_vendoring/attr/_version_info.py

@@ -0,0 +1,86 @@
+# SPDX-License-Identifier: MIT
+
+
+from functools import total_ordering
+
+from ._funcs import astuple
+from ._make import attrib, attrs
+
+
+@total_ordering
+@attrs(eq=False, order=False, slots=True, frozen=True)
+class VersionInfo:
+    """
+    A version object that can be compared to tuple of length 1--4:
+
+    >>> attr.VersionInfo(19, 1, 0, "final")  <= (19, 2)
+    True
+    >>> attr.VersionInfo(19, 1, 0, "final") < (19, 1, 1)
+    True
+    >>> vi = attr.VersionInfo(19, 2, 0, "final")
+    >>> vi < (19, 1, 1)
+    False
+    >>> vi < (19,)
+    False
+    >>> vi == (19, 2,)
+    True
+    >>> vi == (19, 2, 1)
+    False
+
+    .. versionadded:: 19.2
+    """
+
+    year = attrib(type=int)
+    minor = attrib(type=int)
+    micro = attrib(type=int)
+    releaselevel = attrib(type=str)
+
+    @classmethod
+    def _from_version_string(cls, s):
+        """
+        Parse *s* and return a _VersionInfo.
+        """
+        v = s.split(".")
+        if len(v) == 3:
+            v.append("final")
+
+        return cls(
+            year=int(v[0]), minor=int(v[1]), micro=int(v[2]), releaselevel=v[3]
+        )
+
+    def _ensure_tuple(self, other):
+        """
+        Ensure *other* is a tuple of a valid length.
+
+        Returns a possibly transformed *other* and ourselves as a tuple of
+        the same length as *other*.
+        """
+
+        if self.__class__ is other.__class__:
+            other = astuple(other)
+
+        if not isinstance(other, tuple):
+            raise NotImplementedError
+
+        if not (1 <= len(other) <= 4):
+            raise NotImplementedError
+
+        return astuple(self)[: len(other)], other
+
+    def __eq__(self, other):
+        try:
+            us, them = self._ensure_tuple(other)
+        except NotImplementedError:
+            return NotImplemented
+
+        return us == them
+
+    def __lt__(self, other):
+        try:
+            us, them = self._ensure_tuple(other)
+        except NotImplementedError:
+            return NotImplemented
+
+        # Since alphabetically "dev0" < "final" < "post1" < "post2", we don't
+        # have to do anything special with releaselevel for now.
+        return us < them

lib/spack/external/_vendoring/attr/_version_info.pyi

@@ -0,0 +1,9 @@
+class VersionInfo:
+    @property
+    def year(self) -> int: ...
+    @property
+    def minor(self) -> int: ...
+    @property
+    def micro(self) -> int: ...
+    @property
+    def releaselevel(self) -> str: ...

lib/spack/external/_vendoring/attr/converters.py

@@ -0,0 +1,144 @@
+# SPDX-License-Identifier: MIT
+
+"""
+Commonly useful converters.
+"""
+
+
+import typing
+
+from ._compat import _AnnotationExtractor
+from ._make import NOTHING, Factory, pipe
+
+
+__all__ = [
+    "default_if_none",
+    "optional",
+    "pipe",
+    "to_bool",
+]
+
+
+def optional(converter):
+    """
+    A converter that allows an attribute to be optional. An optional attribute
+    is one which can be set to ``None``.
+
+    Type annotations will be inferred from the wrapped converter's, if it
+    has any.
+
+    :param callable converter: the converter that is used for non-``None``
+        values.
+
+    .. versionadded:: 17.1.0
+    """
+
+    def optional_converter(val):
+        if val is None:
+            return None
+        return converter(val)
+
+    xtr = _AnnotationExtractor(converter)
+
+    t = xtr.get_first_param_type()
+    if t:
+        optional_converter.__annotations__["val"] = typing.Optional[t]
+
+    rt = xtr.get_return_type()
+    if rt:
+        optional_converter.__annotations__["return"] = typing.Optional[rt]
+
+    return optional_converter
+
+
+def default_if_none(default=NOTHING, factory=None):
+    """
+    A converter that allows to replace ``None`` values by *default* or the
+    result of *factory*.
+
+    :param default: Value to be used if ``None`` is passed. Passing an instance
+       of `attrs.Factory` is supported, however the ``takes_self`` option
+       is *not*.
+    :param callable factory: A callable that takes no parameters whose result
+       is used if ``None`` is passed.
+
+    :raises TypeError: If **neither** *default* or *factory* is passed.
+    :raises TypeError: If **both** *default* and *factory* are passed.
+    :raises ValueError: If an instance of `attrs.Factory` is passed with
+       ``takes_self=True``.
+
+    .. versionadded:: 18.2.0
+    """
+    if default is NOTHING and factory is None:
+        raise TypeError("Must pass either `default` or `factory`.")
+
+    if default is not NOTHING and factory is not None:
+        raise TypeError(
+            "Must pass either `default` or `factory` but not both."
+        )
+
+    if factory is not None:
+        default = Factory(factory)
+
+    if isinstance(default, Factory):
+        if default.takes_self:
+            raise ValueError(
+                "`takes_self` is not supported by default_if_none."
+            )
+
+        def default_if_none_converter(val):
+            if val is not None:
+                return val
+
+            return default.factory()
+
+    else:
+
+        def default_if_none_converter(val):
+            if val is not None:
+                return val
+
+            return default
+
+    return default_if_none_converter
+
+
+def to_bool(val):
+    """
+    Convert "boolean" strings (e.g., from env. vars.) to real booleans.
+
+    Values mapping to :code:`True`:
+
+    - :code:`True`
+    - :code:`"true"` / :code:`"t"`
+    - :code:`"yes"` / :code:`"y"`
+    - :code:`"on"`
+    - :code:`"1"`
+    - :code:`1`
+
+    Values mapping to :code:`False`:
+
+    - :code:`False`
+    - :code:`"false"` / :code:`"f"`
+    - :code:`"no"` / :code:`"n"`
+    - :code:`"off"`
+    - :code:`"0"`
+    - :code:`0`
+
+    :raises ValueError: for any other value.
+
+    .. versionadded:: 21.3.0
+    """
+    if isinstance(val, str):
+        val = val.lower()
+    truthy = {True, "true", "t", "yes", "y", "on", "1", 1}
+    falsy = {False, "false", "f", "no", "n", "off", "0", 0}
+    try:
+        if val in truthy:
+            return True
+        if val in falsy:
+            return False
+    except TypeError:
+        # Raised when "val" is not hashable (e.g., lists)
+        pass
+    raise ValueError("Cannot convert value to bool: {}".format(val))

lib/spack/external/_vendoring/attr/converters.pyi

@@ -0,0 +1,13 @@
+from typing import Callable, Optional, TypeVar, overload
+
+from . import _ConverterType
+
+_T = TypeVar("_T")
+
+def pipe(*validators: _ConverterType) -> _ConverterType: ...
+def optional(converter: _ConverterType) -> _ConverterType: ...
+@overload
+def default_if_none(default: _T) -> _ConverterType: ...
+@overload
+def default_if_none(*, factory: Callable[[], _T]) -> _ConverterType: ...
+def to_bool(val: str) -> bool: ...

lib/spack/external/_vendoring/attr/exceptions.py

@@ -0,0 +1,92 @@
+# SPDX-License-Identifier: MIT
+
+
+class FrozenError(AttributeError):
+    """
+    A frozen/immutable instance or attribute have been attempted to be
+    modified.
+
+    It mirrors the behavior of ``namedtuples`` by using the same error message
+    and subclassing `AttributeError`.
+
+    .. versionadded:: 20.1.0
+    """
+
+    msg = "can't set attribute"
+    args = [msg]
+
+
+class FrozenInstanceError(FrozenError):
+    """
+    A frozen instance has been attempted to be modified.
+
+    .. versionadded:: 16.1.0
+    """
+
+
+class FrozenAttributeError(FrozenError):
+    """
+    A frozen attribute has been attempted to be modified.
+
+    .. versionadded:: 20.1.0
+    """
+
+
+class AttrsAttributeNotFoundError(ValueError):
+    """
+    An ``attrs`` function couldn't find an attribute that the user asked for.
+
+    .. versionadded:: 16.2.0
+    """
+
+
+class NotAnAttrsClassError(ValueError):
+    """
+    A non-``attrs`` class has been passed into an ``attrs`` function.
+
+    .. versionadded:: 16.2.0
+    """
+
+
+class DefaultAlreadySetError(RuntimeError):
+    """
+    A default has been set using ``attr.ib()`` and is attempted to be reset
+    using the decorator.
+
+    .. versionadded:: 17.1.0
+    """
+
+
+class UnannotatedAttributeError(RuntimeError):
+    """
+    A class with ``auto_attribs=True`` has an ``attr.ib()`` without a type
+    annotation.
+
+    .. versionadded:: 17.3.0
+    """
+
+
+class PythonTooOldError(RuntimeError):
+    """
+    It was attempted to use an ``attrs`` feature that requires a newer Python
+    version.
+
+    .. versionadded:: 18.2.0
+    """
+
+
+class NotCallableError(TypeError):
+    """
+    A ``attr.ib()`` requiring a callable has been set with a value
+    that is not callable.
+
+    .. versionadded:: 19.2.0
+    """
+
+    def __init__(self, msg, value):
+        super(TypeError, self).__init__(msg, value)
+        self.msg = msg
+        self.value = value
+
+    def __str__(self):
+        return str(self.msg)

lib/spack/external/_vendoring/attr/exceptions.pyi

@@ -0,0 +1,17 @@
+from typing import Any
+
+class FrozenError(AttributeError):
+    msg: str = ...
+
+class FrozenInstanceError(FrozenError): ...
+class FrozenAttributeError(FrozenError): ...
+class AttrsAttributeNotFoundError(ValueError): ...
+class NotAnAttrsClassError(ValueError): ...
+class DefaultAlreadySetError(RuntimeError): ...
+class UnannotatedAttributeError(RuntimeError): ...
+class PythonTooOldError(RuntimeError): ...
+
+class NotCallableError(TypeError):
+    msg: str = ...
+    value: Any = ...
+    def __init__(self, msg: str, value: Any) -> None: ...

lib/spack/external/_vendoring/attr/filters.py

@@ -0,0 +1,51 @@
+# SPDX-License-Identifier: MIT
+
+"""
+Commonly useful filters for `attr.asdict`.
+"""
+
+from ._make import Attribute
+
+
+def _split_what(what):
+    """
+    Returns a tuple of `frozenset`s of classes and attributes.
+    """
+    return (
+        frozenset(cls for cls in what if isinstance(cls, type)),
+        frozenset(cls for cls in what if isinstance(cls, Attribute)),
+    )
+
+
+def include(*what):
+    """
+    Include *what*.
+
+    :param what: What to include.
+    :type what: `list` of `type` or `attrs.Attribute`\\ s
+
+    :rtype: `callable`
+    """
+    cls, attrs = _split_what(what)
+
+    def include_(attribute, value):
+        return value.__class__ in cls or attribute in attrs
+
+    return include_
+
+
+def exclude(*what):
+    """
+    Exclude *what*.
+
+    :param what: What to exclude.
+    :type what: `list` of classes or `attrs.Attribute`\\ s.
+
+    :rtype: `callable`
+    """
+    cls, attrs = _split_what(what)
+
+    def exclude_(attribute, value):
+        return value.__class__ not in cls and attribute not in attrs
+
+    return exclude_

lib/spack/external/_vendoring/attr/filters.pyi

@@ -0,0 +1,6 @@
+from typing import Any, Union
+
+from . import Attribute, _FilterType
+
+def include(*what: Union[type, Attribute[Any]]) -> _FilterType[Any]: ...
+def exclude(*what: Union[type, Attribute[Any]]) -> _FilterType[Any]: ...

lib/spack/external/_vendoring/attr/setters.py

@@ -0,0 +1,73 @@
+# SPDX-License-Identifier: MIT
+
+"""
+Commonly used hooks for on_setattr.
+"""
+
+
+from . import _config
+from .exceptions import FrozenAttributeError
+
+
+def pipe(*setters):
+    """
+    Run all *setters* and return the return value of the last one.
+
+    .. versionadded:: 20.1.0
+    """
+
+    def wrapped_pipe(instance, attrib, new_value):
+        rv = new_value
+
+        for setter in setters:
+            rv = setter(instance, attrib, rv)
+
+        return rv
+
+    return wrapped_pipe
+
+
+def frozen(_, __, ___):
+    """
+    Prevent an attribute to be modified.
+
+    .. versionadded:: 20.1.0
+    """
+    raise FrozenAttributeError()
+
+
+def validate(instance, attrib, new_value):
+    """
+    Run *attrib*'s validator on *new_value* if it has one.
+
+    .. versionadded:: 20.1.0
+    """
+    if _config._run_validators is False:
+        return new_value
+
+    v = attrib.validator
+    if not v:
+        return new_value
+
+    v(instance, attrib, new_value)
+
+    return new_value
+
+
+def convert(instance, attrib, new_value):
+    """
+    Run *attrib*'s converter -- if it has one --  on *new_value* and return the
+    result.
+
+    .. versionadded:: 20.1.0
+    """
+    c = attrib.converter
+    if c:
+        return c(new_value)
+
+    return new_value
+
+
+# Sentinel for disabling class-wide *on_setattr* hooks for certain attributes.
+# autodata stopped working, so the docstring is inlined in the API docs.
+NO_OP = object()

lib/spack/external/_vendoring/attr/setters.pyi

@@ -0,0 +1,19 @@
+from typing import Any, NewType, NoReturn, TypeVar, cast
+
+from . import Attribute, _OnSetAttrType
+
+_T = TypeVar("_T")
+
+def frozen(
+    instance: Any, attribute: Attribute[Any], new_value: Any
+) -> NoReturn: ...
+def pipe(*setters: _OnSetAttrType) -> _OnSetAttrType: ...
+def validate(instance: Any, attribute: Attribute[_T], new_value: _T) -> _T: ...
+
+# convert is allowed to return Any, because they can be chained using pipe.
+def convert(
+    instance: Any, attribute: Attribute[Any], new_value: Any
+) -> Any: ...
+
+_NoOpType = NewType("_NoOpType", object)
+NO_OP: _NoOpType

lib/spack/external/_vendoring/attr/validators.py

@@ -0,0 +1,594 @@
+# SPDX-License-Identifier: MIT
+
+"""
+Commonly useful validators.
+"""
+
+
+import operator
+import re
+
+from contextlib import contextmanager
+
+from ._config import get_run_validators, set_run_validators
+from ._make import _AndValidator, and_, attrib, attrs
+from .exceptions import NotCallableError
+
+
+try:
+    Pattern = re.Pattern
+except AttributeError:  # Python <3.7 lacks a Pattern type.
+    Pattern = type(re.compile(""))
+
+
+__all__ = [
+    "and_",
+    "deep_iterable",
+    "deep_mapping",
+    "disabled",
+    "ge",
+    "get_disabled",
+    "gt",
+    "in_",
+    "instance_of",
+    "is_callable",
+    "le",
+    "lt",
+    "matches_re",
+    "max_len",
+    "min_len",
+    "optional",
+    "provides",
+    "set_disabled",
+]
+
+
+def set_disabled(disabled):
+    """
+    Globally disable or enable running validators.
+
+    By default, they are run.
+
+    :param disabled: If ``True``, disable running all validators.
+    :type disabled: bool
+
+    .. warning::
+
+        This function is not thread-safe!
+
+    .. versionadded:: 21.3.0
+    """
+    set_run_validators(not disabled)
+
+
+def get_disabled():
+    """
+    Return a bool indicating whether validators are currently disabled or not.
+
+    :return: ``True`` if validators are currently disabled.
+    :rtype: bool
+
+    .. versionadded:: 21.3.0
+    """
+    return not get_run_validators()
+
+
+@contextmanager
+def disabled():
+    """
+    Context manager that disables running validators within its context.
+
+    .. warning::
+
+        This context manager is not thread-safe!
+
+    .. versionadded:: 21.3.0
+    """
+    set_run_validators(False)
+    try:
+        yield
+    finally:
+        set_run_validators(True)
+
+
+@attrs(repr=False, slots=True, hash=True)
+class _InstanceOfValidator:
+    type = attrib()
+
+    def __call__(self, inst, attr, value):
+        """
+        We use a callable class to be able to change the ``__repr__``.
+        """
+        if not isinstance(value, self.type):
+            raise TypeError(
+                "'{name}' must be {type!r} (got {value!r} that is a "
+                "{actual!r}).".format(
+                    name=attr.name,
+                    type=self.type,
+                    actual=value.__class__,
+                    value=value,
+                ),
+                attr,
+                self.type,
+                value,
+            )
+
+    def __repr__(self):
+        return "<instance_of validator for type {type!r}>".format(
+            type=self.type
+        )
+
+
+def instance_of(type):
+    """
+    A validator that raises a `TypeError` if the initializer is called
+    with a wrong type for this particular attribute (checks are performed using
+    `isinstance` therefore it's also valid to pass a tuple of types).
+
+    :param type: The type to check for.
+    :type type: type or tuple of types
+
+    :raises TypeError: With a human readable error message, the attribute
+        (of type `attrs.Attribute`), the expected type, and the value it
+        got.
+    """
+    return _InstanceOfValidator(type)
+
+
+@attrs(repr=False, frozen=True, slots=True)
+class _MatchesReValidator:
+    pattern = attrib()
+    match_func = attrib()
+
+    def __call__(self, inst, attr, value):
+        """
+        We use a callable class to be able to change the ``__repr__``.
+        """
+        if not self.match_func(value):
+            raise ValueError(
+                "'{name}' must match regex {pattern!r}"
+                " ({value!r} doesn't)".format(
+                    name=attr.name, pattern=self.pattern.pattern, value=value
+                ),
+                attr,
+                self.pattern,
+                value,
+            )
+
+    def __repr__(self):
+        return "<matches_re validator for pattern {pattern!r}>".format(
+            pattern=self.pattern
+        )
+
+
+def matches_re(regex, flags=0, func=None):
+    r"""
+    A validator that raises `ValueError` if the initializer is called
+    with a string that doesn't match *regex*.
+
+    :param regex: a regex string or precompiled pattern to match against
+    :param int flags: flags that will be passed to the underlying re function
+        (default 0)
+    :param callable func: which underlying `re` function to call. Valid options
+        are `re.fullmatch`, `re.search`, and `re.match`; the default ``None``
+        means `re.fullmatch`. For performance reasons, the pattern is always
+        precompiled using `re.compile`.
+
+    .. versionadded:: 19.2.0
+    .. versionchanged:: 21.3.0 *regex* can be a pre-compiled pattern.
+    """
+    valid_funcs = (re.fullmatch, None, re.search, re.match)
+    if func not in valid_funcs:
+        raise ValueError(
+            "'func' must be one of {}.".format(
+                ", ".join(
+                    sorted(
+                        e and e.__name__ or "None" for e in set(valid_funcs)
+                    )
+                )
+            )
+        )
+
+    if isinstance(regex, Pattern):
+        if flags:
+            raise TypeError(
+                "'flags' can only be used with a string pattern; "
+                "pass flags to re.compile() instead"
+            )
+        pattern = regex
+    else:
+        pattern = re.compile(regex, flags)
+
+    if func is re.match:
+        match_func = pattern.match
+    elif func is re.search:
+        match_func = pattern.search
+    else:
+        match_func = pattern.fullmatch
+
+    return _MatchesReValidator(pattern, match_func)
+
+
+@attrs(repr=False, slots=True, hash=True)
+class _ProvidesValidator:
+    interface = attrib()
+
+    def __call__(self, inst, attr, value):
+        """
+        We use a callable class to be able to change the ``__repr__``.
+        """
+        if not self.interface.providedBy(value):
+            raise TypeError(
+                "'{name}' must provide {interface!r} which {value!r} "
+                "doesn't.".format(
+                    name=attr.name, interface=self.interface, value=value
+                ),
+                attr,
+                self.interface,
+                value,
+            )
+
+    def __repr__(self):
+        return "<provides validator for interface {interface!r}>".format(
+            interface=self.interface
+        )
+
+
+def provides(interface):
+    """
+    A validator that raises a `TypeError` if the initializer is called
+    with an object that does not provide the requested *interface* (checks are
+    performed using ``interface.providedBy(value)`` (see `zope.interface
+    <https://zopeinterface.readthedocs.io/en/latest/>`_).
+
+    :param interface: The interface to check for.
+    :type interface: ``zope.interface.Interface``
+
+    :raises TypeError: With a human readable error message, the attribute
+        (of type `attrs.Attribute`), the expected interface, and the
+        value it got.
+    """
+    return _ProvidesValidator(interface)
+
+
+@attrs(repr=False, slots=True, hash=True)
+class _OptionalValidator:
+    validator = attrib()
+
+    def __call__(self, inst, attr, value):
+        if value is None:
+            return
+
+        self.validator(inst, attr, value)
+
+    def __repr__(self):
+        return "<optional validator for {what} or None>".format(
+            what=repr(self.validator)
+        )
+
+
+def optional(validator):
+    """
+    A validator that makes an attribute optional.  An optional attribute is one
+    which can be set to ``None`` in addition to satisfying the requirements of
+    the sub-validator.
+
+    :param validator: A validator (or a list of validators) that is used for
+        non-``None`` values.
+    :type validator: callable or `list` of callables.
+
+    .. versionadded:: 15.1.0
+    .. versionchanged:: 17.1.0 *validator* can be a list of validators.
+    """
+    if isinstance(validator, list):
+        return _OptionalValidator(_AndValidator(validator))
+    return _OptionalValidator(validator)
+
+
+@attrs(repr=False, slots=True, hash=True)
+class _InValidator:
+    options = attrib()
+
+    def __call__(self, inst, attr, value):
+        try:
+            in_options = value in self.options
+        except TypeError:  # e.g. `1 in "abc"`
+            in_options = False
+
+        if not in_options:
+            raise ValueError(
+                "'{name}' must be in {options!r} (got {value!r})".format(
+                    name=attr.name, options=self.options, value=value
+                ),
+                attr,
+                self.options,
+                value,
+            )
+
+    def __repr__(self):
+        return "<in_ validator with options {options!r}>".format(
+            options=self.options
+        )
+
+
+def in_(options):
+    """
+    A validator that raises a `ValueError` if the initializer is called
+    with a value that does not belong in the options provided.  The check is
+    performed using ``value in options``.
+
+    :param options: Allowed options.
+    :type options: list, tuple, `enum.Enum`, ...
+
+    :raises ValueError: With a human readable error message, the attribute (of
+       type `attrs.Attribute`), the expected options, and the value it
+       got.
+
+    .. versionadded:: 17.1.0
+    .. versionchanged:: 22.1.0
+       The ValueError was incomplete until now and only contained the human
+       readable error message. Now it contains all the information that has
+       been promised since 17.1.0.
+    """
+    return _InValidator(options)
+
+
+@attrs(repr=False, slots=False, hash=True)
+class _IsCallableValidator:
+    def __call__(self, inst, attr, value):
+        """
+        We use a callable class to be able to change the ``__repr__``.
+        """
+        if not callable(value):
+            message = (
+                "'{name}' must be callable "
+                "(got {value!r} that is a {actual!r})."
+            )
+            raise NotCallableError(
+                msg=message.format(
+                    name=attr.name, value=value, actual=value.__class__
+                ),
+                value=value,
+            )
+
+    def __repr__(self):
+        return "<is_callable validator>"
+
+
+def is_callable():
+    """
+    A validator that raises a `attr.exceptions.NotCallableError` if the
+    initializer is called with a value for this particular attribute
+    that is not callable.
+
+    .. versionadded:: 19.1.0
+
+    :raises `attr.exceptions.NotCallableError`: With a human readable error
+        message containing the attribute (`attrs.Attribute`) name,
+        and the value it got.
+    """
+    return _IsCallableValidator()
+
+
+@attrs(repr=False, slots=True, hash=True)
+class _DeepIterable:
+    member_validator = attrib(validator=is_callable())
+    iterable_validator = attrib(
+        default=None, validator=optional(is_callable())
+    )
+
+    def __call__(self, inst, attr, value):
+        """
+        We use a callable class to be able to change the ``__repr__``.
+        """
+        if self.iterable_validator is not None:
+            self.iterable_validator(inst, attr, value)
+
+        for member in value:
+            self.member_validator(inst, attr, member)
+
+    def __repr__(self):
+        iterable_identifier = (
+            ""
+            if self.iterable_validator is None
+            else " {iterable!r}".format(iterable=self.iterable_validator)
+        )
+        return (
+            "<deep_iterable validator for{iterable_identifier}"
+            " iterables of {member!r}>"
+        ).format(
+            iterable_identifier=iterable_identifier,
+            member=self.member_validator,
+        )
+
+
+def deep_iterable(member_validator, iterable_validator=None):
+    """
+    A validator that performs deep validation of an iterable.
+
+    :param member_validator: Validator(s) to apply to iterable members
+    :param iterable_validator: Validator to apply to iterable itself
+        (optional)
+
+    .. versionadded:: 19.1.0
+
+    :raises TypeError: if any sub-validators fail
+    """
+    if isinstance(member_validator, (list, tuple)):
+        member_validator = and_(*member_validator)
+    return _DeepIterable(member_validator, iterable_validator)
+
+
+@attrs(repr=False, slots=True, hash=True)
+class _DeepMapping:
+    key_validator = attrib(validator=is_callable())
+    value_validator = attrib(validator=is_callable())
+    mapping_validator = attrib(default=None, validator=optional(is_callable()))
+
+    def __call__(self, inst, attr, value):
+        """
+        We use a callable class to be able to change the ``__repr__``.
+        """
+        if self.mapping_validator is not None:
+            self.mapping_validator(inst, attr, value)
+
+        for key in value:
+            self.key_validator(inst, attr, key)
+            self.value_validator(inst, attr, value[key])
+
+    def __repr__(self):
+        return (
+            "<deep_mapping validator for objects mapping {key!r} to {value!r}>"
+        ).format(key=self.key_validator, value=self.value_validator)
+
+
+def deep_mapping(key_validator, value_validator, mapping_validator=None):
+    """
+    A validator that performs deep validation of a dictionary.
+
+    :param key_validator: Validator to apply to dictionary keys
+    :param value_validator: Validator to apply to dictionary values
+    :param mapping_validator: Validator to apply to top-level mapping
+        attribute (optional)
+
+    .. versionadded:: 19.1.0
+
+    :raises TypeError: if any sub-validators fail
+    """
+    return _DeepMapping(key_validator, value_validator, mapping_validator)
+
+
+@attrs(repr=False, frozen=True, slots=True)
+class _NumberValidator:
+    bound = attrib()
+    compare_op = attrib()
+    compare_func = attrib()
+
+    def __call__(self, inst, attr, value):
+        """
+        We use a callable class to be able to change the ``__repr__``.
+        """
+        if not self.compare_func(value, self.bound):
+            raise ValueError(
+                "'{name}' must be {op} {bound}: {value}".format(
+                    name=attr.name,
+                    op=self.compare_op,
+                    bound=self.bound,
+                    value=value,
+                )
+            )
+
+    def __repr__(self):
+        return "<Validator for x {op} {bound}>".format(
+            op=self.compare_op, bound=self.bound
+        )
+
+
+def lt(val):
+    """
+    A validator that raises `ValueError` if the initializer is called
+    with a number larger or equal to *val*.
+
+    :param val: Exclusive upper bound for values
+
+    .. versionadded:: 21.3.0
+    """
+    return _NumberValidator(val, "<", operator.lt)
+
+
+def le(val):
+    """
+    A validator that raises `ValueError` if the initializer is called
+    with a number greater than *val*.
+
+    :param val: Inclusive upper bound for values
+
+    .. versionadded:: 21.3.0
+    """
+    return _NumberValidator(val, "<=", operator.le)
+
+
+def ge(val):
+    """
+    A validator that raises `ValueError` if the initializer is called
+    with a number smaller than *val*.
+
+    :param val: Inclusive lower bound for values
+
+    .. versionadded:: 21.3.0
+    """
+    return _NumberValidator(val, ">=", operator.ge)
+
+
+def gt(val):
+    """
+    A validator that raises `ValueError` if the initializer is called
+    with a number smaller or equal to *val*.
+
+    :param val: Exclusive lower bound for values
+
+    .. versionadded:: 21.3.0
+    """
+    return _NumberValidator(val, ">", operator.gt)
+
+
+@attrs(repr=False, frozen=True, slots=True)
+class _MaxLengthValidator:
+    max_length = attrib()
+
+    def __call__(self, inst, attr, value):
+        """
+        We use a callable class to be able to change the ``__repr__``.
+        """
+        if len(value) > self.max_length:
+            raise ValueError(
+                "Length of '{name}' must be <= {max}: {len}".format(
+                    name=attr.name, max=self.max_length, len=len(value)
+                )
+            )
+
+    def __repr__(self):
+        return "<max_len validator for {max}>".format(max=self.max_length)
+
+
+def max_len(length):
+    """
+    A validator that raises `ValueError` if the initializer is called
+    with a string or iterable that is longer than *length*.
+
+    :param int length: Maximum length of the string or iterable
+
+    .. versionadded:: 21.3.0
+    """
+    return _MaxLengthValidator(length)
+
+
+@attrs(repr=False, frozen=True, slots=True)
+class _MinLengthValidator:
+    min_length = attrib()
+
+    def __call__(self, inst, attr, value):
+        """
+        We use a callable class to be able to change the ``__repr__``.
+        """
+        if len(value) < self.min_length:
+            raise ValueError(
+                "Length of '{name}' must be => {min}: {len}".format(
+                    name=attr.name, min=self.min_length, len=len(value)
+                )
+            )
+
+    def __repr__(self):
+        return "<min_len validator for {min}>".format(min=self.min_length)
+
+
+def min_len(length):
+    """
+    A validator that raises `ValueError` if the initializer is called
+    with a string or iterable that is shorter than *length*.
+
+    :param int length: Minimum length of the string or iterable
+
+    .. versionadded:: 22.1.0
+    """
+    return _MinLengthValidator(length)

lib/spack/external/_vendoring/attr/validators.pyi

@@ -0,0 +1,80 @@
+from typing import (
+    Any,
+    AnyStr,
+    Callable,
+    Container,
+    ContextManager,
+    Iterable,
+    List,
+    Mapping,
+    Match,
+    Optional,
+    Pattern,
+    Tuple,
+    Type,
+    TypeVar,
+    Union,
+    overload,
+)
+
+from . import _ValidatorType
+from . import _ValidatorArgType
+
+_T = TypeVar("_T")
+_T1 = TypeVar("_T1")
+_T2 = TypeVar("_T2")
+_T3 = TypeVar("_T3")
+_I = TypeVar("_I", bound=Iterable)
+_K = TypeVar("_K")
+_V = TypeVar("_V")
+_M = TypeVar("_M", bound=Mapping)
+
+def set_disabled(run: bool) -> None: ...
+def get_disabled() -> bool: ...
+def disabled() -> ContextManager[None]: ...
+
+# To be more precise on instance_of use some overloads.
+# If there are more than 3 items in the tuple then we fall back to Any
+@overload
+def instance_of(type: Type[_T]) -> _ValidatorType[_T]: ...
+@overload
+def instance_of(type: Tuple[Type[_T]]) -> _ValidatorType[_T]: ...
+@overload
+def instance_of(
+    type: Tuple[Type[_T1], Type[_T2]]
+) -> _ValidatorType[Union[_T1, _T2]]: ...
+@overload
+def instance_of(
+    type: Tuple[Type[_T1], Type[_T2], Type[_T3]]
+) -> _ValidatorType[Union[_T1, _T2, _T3]]: ...
+@overload
+def instance_of(type: Tuple[type, ...]) -> _ValidatorType[Any]: ...
+def provides(interface: Any) -> _ValidatorType[Any]: ...
+def optional(
+    validator: Union[_ValidatorType[_T], List[_ValidatorType[_T]]]
+) -> _ValidatorType[Optional[_T]]: ...
+def in_(options: Container[_T]) -> _ValidatorType[_T]: ...
+def and_(*validators: _ValidatorType[_T]) -> _ValidatorType[_T]: ...
+def matches_re(
+    regex: Union[Pattern[AnyStr], AnyStr],
+    flags: int = ...,
+    func: Optional[
+        Callable[[AnyStr, AnyStr, int], Optional[Match[AnyStr]]]
+    ] = ...,
+) -> _ValidatorType[AnyStr]: ...
+def deep_iterable(
+    member_validator: _ValidatorArgType[_T],
+    iterable_validator: Optional[_ValidatorType[_I]] = ...,
+) -> _ValidatorType[_I]: ...
+def deep_mapping(
+    key_validator: _ValidatorType[_K],
+    value_validator: _ValidatorType[_V],
+    mapping_validator: Optional[_ValidatorType[_M]] = ...,
+) -> _ValidatorType[_M]: ...
+def is_callable() -> _ValidatorType[_T]: ...
+def lt(val: _T) -> _ValidatorType[_T]: ...
+def le(val: _T) -> _ValidatorType[_T]: ...
+def ge(val: _T) -> _ValidatorType[_T]: ...
+def gt(val: _T) -> _ValidatorType[_T]: ...
+def max_len(length: int) -> _ValidatorType[_T]: ...
+def min_len(length: int) -> _ValidatorType[_T]: ...

lib/spack/external/_vendoring/attrs/LICENSE

@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2015 Hynek Schlawack and the attrs contributors
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

lib/spack/external/_vendoring/attrs/__init__.py

@@ -0,0 +1,70 @@
+# SPDX-License-Identifier: MIT
+
+from attr import (
+    NOTHING,
+    Attribute,
+    Factory,
+    __author__,
+    __copyright__,
+    __description__,
+    __doc__,
+    __email__,
+    __license__,
+    __title__,
+    __url__,
+    __version__,
+    __version_info__,
+    assoc,
+    cmp_using,
+    define,
+    evolve,
+    field,
+    fields,
+    fields_dict,
+    frozen,
+    has,
+    make_class,
+    mutable,
+    resolve_types,
+    validate,
+)
+from attr._next_gen import asdict, astuple
+
+from . import converters, exceptions, filters, setters, validators
+
+
+__all__ = [
+    "__author__",
+    "__copyright__",
+    "__description__",
+    "__doc__",
+    "__email__",
+    "__license__",
+    "__title__",
+    "__url__",
+    "__version__",
+    "__version_info__",
+    "asdict",
+    "assoc",
+    "astuple",
+    "Attribute",
+    "cmp_using",
+    "converters",
+    "define",
+    "evolve",
+    "exceptions",
+    "Factory",
+    "field",
+    "fields_dict",
+    "fields",
+    "filters",
+    "frozen",
+    "has",
+    "make_class",
+    "mutable",
+    "NOTHING",
+    "resolve_types",
+    "setters",
+    "validate",
+    "validators",
+]

lib/spack/external/_vendoring/attrs/__init__.pyi

@@ -0,0 +1,66 @@
+from typing import (
+    Any,
+    Callable,
+    Dict,
+    Mapping,
+    Optional,
+    Sequence,
+    Tuple,
+    Type,
+)
+
+# Because we need to type our own stuff, we have to make everything from
+# attr explicitly public too.
+from attr import __author__ as __author__
+from attr import __copyright__ as __copyright__
+from attr import __description__ as __description__
+from attr import __email__ as __email__
+from attr import __license__ as __license__
+from attr import __title__ as __title__
+from attr import __url__ as __url__
+from attr import __version__ as __version__
+from attr import __version_info__ as __version_info__
+from attr import _FilterType
+from attr import assoc as assoc
+from attr import Attribute as Attribute
+from attr import cmp_using as cmp_using
+from attr import converters as converters
+from attr import define as define
+from attr import evolve as evolve
+from attr import exceptions as exceptions
+from attr import Factory as Factory
+from attr import field as field
+from attr import fields as fields
+from attr import fields_dict as fields_dict
+from attr import filters as filters
+from attr import frozen as frozen
+from attr import has as has
+from attr import make_class as make_class
+from attr import mutable as mutable
+from attr import NOTHING as NOTHING
+from attr import resolve_types as resolve_types
+from attr import setters as setters
+from attr import validate as validate
+from attr import validators as validators
+
+# TODO: see definition of attr.asdict/astuple
+def asdict(
+    inst: Any,
+    recurse: bool = ...,
+    filter: Optional[_FilterType[Any]] = ...,
+    dict_factory: Type[Mapping[Any, Any]] = ...,
+    retain_collection_types: bool = ...,
+    value_serializer: Optional[
+        Callable[[type, Attribute[Any], Any], Any]
+    ] = ...,
+    tuple_keys: bool = ...,
+) -> Dict[str, Any]: ...
+
+# TODO: add support for returning NamedTuple from the mypy plugin
+def astuple(
+    inst: Any,
+    recurse: bool = ...,
+    filter: Optional[_FilterType[Any]] = ...,
+    tuple_factory: Type[Sequence[Any]] = ...,
+    retain_collection_types: bool = ...,
+) -> Tuple[Any, ...]: ...

lib/spack/external/_vendoring/attrs/converters.py

@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: MIT
+
+from attr.converters import *  # noqa

lib/spack/external/_vendoring/attrs/exceptions.py

@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: MIT
+
+from attr.exceptions import *  # noqa

lib/spack/external/_vendoring/attrs/filters.py

@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: MIT
+
+from attr.filters import *  # noqa

lib/spack/external/_vendoring/attrs/setters.py

@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: MIT
+
+from attr.setters import *  # noqa

lib/spack/external/_vendoring/attrs/validators.py

@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: MIT
+
+from attr.validators import *  # noqa

lib/spack/external/_vendoring/distro/LICENSE

@@ -0,0 +1,202 @@
+Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
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+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
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+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
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+
+      "Work" shall mean the work of authorship, whether in Source or
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+      "Contribution" shall mean any work of authorship, including
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+   END OF TERMS AND CONDITIONS
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+   See the License for the specific language governing permissions and
+   limitations under the License.
+

lib/spack/external/_vendoring/distro/__init__.py

@@ -0,0 +1,54 @@
+from .distro import (
+    NORMALIZED_DISTRO_ID,
+    NORMALIZED_LSB_ID,
+    NORMALIZED_OS_ID,
+    LinuxDistribution,
+    __version__,
+    build_number,
+    codename,
+    distro_release_attr,
+    distro_release_info,
+    id,
+    info,
+    like,
+    linux_distribution,
+    lsb_release_attr,
+    lsb_release_info,
+    major_version,
+    minor_version,
+    name,
+    os_release_attr,
+    os_release_info,
+    uname_attr,
+    uname_info,
+    version,
+    version_parts,
+)
+
+__all__ = [
+    "NORMALIZED_DISTRO_ID",
+    "NORMALIZED_LSB_ID",
+    "NORMALIZED_OS_ID",
+    "LinuxDistribution",
+    "build_number",
+    "codename",
+    "distro_release_attr",
+    "distro_release_info",
+    "id",
+    "info",
+    "like",
+    "linux_distribution",
+    "lsb_release_attr",
+    "lsb_release_info",
+    "major_version",
+    "minor_version",
+    "name",
+    "os_release_attr",
+    "os_release_info",
+    "uname_attr",
+    "uname_info",
+    "version",
+    "version_parts",
+]
+
+__version__ = __version__

lib/spack/external/_vendoring/distro/__main__.py

@@ -0,0 +1,4 @@
+from .distro import main
+
+if __name__ == "__main__":
+    main()

lib/spack/external/_vendoring/jinja2/LICENSE.rst

@@ -0,0 +1,28 @@
+Copyright 2007 Pallets
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+1.  Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+2.  Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in the
+    documentation and/or other materials provided with the distribution.
+
+3.  Neither the name of the copyright holder nor the names of its
+    contributors may be used to endorse or promote products derived from
+    this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
+TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

lib/spack/external/_vendoring/jinja2/__init__.py

@@ -0,0 +1,45 @@
+"""Jinja is a template engine written in pure Python. It provides a
+non-XML syntax that supports inline expressions and an optional
+sandboxed environment.
+"""
+from .bccache import BytecodeCache as BytecodeCache
+from .bccache import FileSystemBytecodeCache as FileSystemBytecodeCache
+from .bccache import MemcachedBytecodeCache as MemcachedBytecodeCache
+from .environment import Environment as Environment
+from .environment import Template as Template
+from .exceptions import TemplateAssertionError as TemplateAssertionError
+from .exceptions import TemplateError as TemplateError
+from .exceptions import TemplateNotFound as TemplateNotFound
+from .exceptions import TemplateRuntimeError as TemplateRuntimeError
+from .exceptions import TemplatesNotFound as TemplatesNotFound
+from .exceptions import TemplateSyntaxError as TemplateSyntaxError
+from .exceptions import UndefinedError as UndefinedError
+from .filters import contextfilter
+from .filters import environmentfilter
+from .filters import evalcontextfilter
+from .loaders import BaseLoader as BaseLoader
+from .loaders import ChoiceLoader as ChoiceLoader
+from .loaders import DictLoader as DictLoader
+from .loaders import FileSystemLoader as FileSystemLoader
+from .loaders import FunctionLoader as FunctionLoader
+from .loaders import ModuleLoader as ModuleLoader
+from .loaders import PackageLoader as PackageLoader
+from .loaders import PrefixLoader as PrefixLoader
+from .runtime import ChainableUndefined as ChainableUndefined
+from .runtime import DebugUndefined as DebugUndefined
+from .runtime import make_logging_undefined as make_logging_undefined
+from .runtime import StrictUndefined as StrictUndefined
+from .runtime import Undefined as Undefined
+from .utils import clear_caches as clear_caches
+from .utils import contextfunction
+from .utils import environmentfunction
+from .utils import escape
+from .utils import evalcontextfunction
+from .utils import is_undefined as is_undefined
+from .utils import Markup
+from .utils import pass_context as pass_context
+from .utils import pass_environment as pass_environment
+from .utils import pass_eval_context as pass_eval_context
+from .utils import select_autoescape as select_autoescape
+
+__version__ = "3.0.3"

lib/spack/external/_vendoring/jinja2/_identifier.py

@@ -0,0 +1,6 @@
+import re
+
+# generated by scripts/generate_identifier_pattern.py
+pattern = re.compile(
+    r"[\w·̀-ͯ·҃-֑҇-ׇֽֿׁׂׅׄؐ-ًؚ-ٰٟۖ-ۜ۟-۪ۤۧۨ-ܑۭܰ-݊ަ-ް߫-߳ࠖ-࠙ࠛ-ࠣࠥ-ࠧࠩ-࡙࠭-࡛ࣔ-ࣣ࣡-ःऺ-़ा-ॏ॑-ॗॢॣঁ-ঃ়া-ৄেৈো-্ৗৢৣਁ-ਃ਼ਾ-ੂੇੈੋ-੍ੑੰੱੵઁ-ઃ઼ા-ૅે-ૉો-્ૢૣଁ-ଃ଼ା-ୄେୈୋ-୍ୖୗୢୣஂா-ூெ-ைொ-்ௗఀ-ఃా-ౄె-ైొ-్ౕౖౢౣಁ-ಃ಼ಾ-ೄೆ-ೈೊ-್ೕೖೢೣഁ-ഃാ-ൄെ-ൈൊ-്ൗൢൣංඃ්ා-ුූෘ-ෟෲෳัิ-ฺ็-๎ັິ-ູົຼ່-ໍ༹༘༙༵༷༾༿ཱ-྄྆྇ྍ-ྗྙ-ྼ࿆ါ-ှၖ-ၙၞ-ၠၢ-ၤၧ-ၭၱ-ၴႂ-ႍႏႚ-ႝ፝-፟ᜒ-᜔ᜲ-᜴ᝒᝓᝲᝳ឴-៓៝᠋-᠍ᢅᢆᢩᤠ-ᤫᤰ-᤻ᨗ-ᨛᩕ-ᩞ᩠-᩿᩼᪰-᪽ᬀ-ᬄ᬴-᭄᭫-᭳ᮀ-ᮂᮡ-ᮭ᯦-᯳ᰤ-᰷᳐-᳔᳒-᳨᳭ᳲ-᳴᳸᳹᷀-᷵᷻-᷿‿⁀⁔⃐-⃥⃜⃡-⃰℘℮⳯-⵿⳱ⷠ-〪ⷿ-゙゚〯꙯ꙴ-꙽ꚞꚟ꛰꛱ꠂ꠆ꠋꠣ-ꠧꢀꢁꢴ-ꣅ꣠-꣱ꤦ-꤭ꥇ-꥓ꦀ-ꦃ꦳-꧀ꧥꨩ-ꨶꩃꩌꩍꩻ-ꩽꪰꪲ-ꪴꪷꪸꪾ꪿꫁ꫫ-ꫯꫵ꫶ꯣ-ꯪ꯬꯭ﬞ︀-️︠-︯︳︴﹍-﹏＿𐇽𐋠𐍶-𐍺𐨁-𐨃𐨅𐨆𐨌-𐨏𐨸-𐨿𐨺𐫦𐫥𑀀-𑀂𑀸-𑁆𑁿-𑂂𑂰-𑂺𑄀-𑄂𑄧-𑅳𑄴𑆀-𑆂𑆳-𑇊𑇀-𑇌𑈬-𑈷𑈾𑋟-𑋪𑌀-𑌃𑌼𑌾-𑍄𑍇𑍈𑍋-𑍍𑍗𑍢𑍣𑍦-𑍬𑍰-𑍴𑐵-𑑆𑒰-𑓃𑖯-𑖵𑖸-𑗀𑗜𑗝𑘰-𑙀𑚫-𑚷𑜝-𑜫𑰯-𑰶𑰸-𑰿𑲒-𑲧𑲩-𑲶𖫰-𖫴𖬰-𖬶𖽑-𖽾𖾏-𖾒𛲝𛲞𝅥-𝅩𝅭-𝅲𝅻-𝆂𝆅-𝆋𝆪-𝆭𝉂-𝉄𝨀-𝨶𝨻-𝩬𝩵𝪄𝪛-𝪟𝪡-𝪯𞀀-𞀆𞀈-𞀘𞀛-𞀡𞀣𞀤𞀦-𞣐𞀪-𞣖𞥄-𞥊󠄀-󠇯]+"  # noqa: B950
+)

lib/spack/external/_vendoring/jinja2/async_utils.py

@@ -0,0 +1,75 @@
+import inspect
+import typing as t
+from functools import wraps
+
+from .utils import _PassArg
+from .utils import pass_eval_context
+
+V = t.TypeVar("V")
+
+
+def async_variant(normal_func):  # type: ignore
+    def decorator(async_func):  # type: ignore
+        pass_arg = _PassArg.from_obj(normal_func)
+        need_eval_context = pass_arg is None
+
+        if pass_arg is _PassArg.environment:
+
+            def is_async(args: t.Any) -> bool:
+                return t.cast(bool, args[0].is_async)
+
+        else:
+
+            def is_async(args: t.Any) -> bool:
+                return t.cast(bool, args[0].environment.is_async)
+
+        @wraps(normal_func)
+        def wrapper(*args, **kwargs):  # type: ignore
+            b = is_async(args)
+
+            if need_eval_context:
+                args = args[1:]
+
+            if b:
+                return async_func(*args, **kwargs)
+
+            return normal_func(*args, **kwargs)
+
+        if need_eval_context:
+            wrapper = pass_eval_context(wrapper)
+
+        wrapper.jinja_async_variant = True
+        return wrapper
+
+    return decorator
+
+
+_common_primitives = {int, float, bool, str, list, dict, tuple, type(None)}
+
+
+async def auto_await(value: t.Union[t.Awaitable["V"], "V"]) -> "V":
+    # Avoid a costly call to isawaitable
+    if type(value) in _common_primitives:
+        return t.cast("V", value)
+
+    if inspect.isawaitable(value):
+        return await t.cast("t.Awaitable[V]", value)
+
+    return t.cast("V", value)
+
+
+async def auto_aiter(
+    iterable: "t.Union[t.AsyncIterable[V], t.Iterable[V]]",
+) -> "t.AsyncIterator[V]":
+    if hasattr(iterable, "__aiter__"):
+        async for item in t.cast("t.AsyncIterable[V]", iterable):
+            yield item
+    else:
+        for item in t.cast("t.Iterable[V]", iterable):
+            yield item
+
+
+async def auto_to_list(
+    value: "t.Union[t.AsyncIterable[V], t.Iterable[V]]",
+) -> t.List["V"]:
+    return [x async for x in auto_aiter(value)]

lib/spack/external/_vendoring/jinja2/bccache.py

@@ -0,0 +1,364 @@
+"""The optional bytecode cache system. This is useful if you have very
+complex template situations and the compilation of all those templates
+slows down your application too much.
+
+Situations where this is useful are often forking web applications that
+are initialized on the first request.
+"""
+import errno
+import fnmatch
+import marshal
+import os
+import pickle
+import stat
+import sys
+import tempfile
+import typing as t
+from hashlib import sha1
+from io import BytesIO
+from types import CodeType
+
+if t.TYPE_CHECKING:
+    import typing_extensions as te
+    from .environment import Environment
+
+    class _MemcachedClient(te.Protocol):
+        def get(self, key: str) -> bytes:
+            ...
+
+        def set(self, key: str, value: bytes, timeout: t.Optional[int] = None) -> None:
+            ...
+
+
+bc_version = 5
+# Magic bytes to identify Jinja bytecode cache files. Contains the
+# Python major and minor version to avoid loading incompatible bytecode
+# if a project upgrades its Python version.
+bc_magic = (
+    b"j2"
+    + pickle.dumps(bc_version, 2)
+    + pickle.dumps((sys.version_info[0] << 24) | sys.version_info[1], 2)
+)
+
+
+class Bucket:
+    """Buckets are used to store the bytecode for one template.  It's created
+    and initialized by the bytecode cache and passed to the loading functions.
+
+    The buckets get an internal checksum from the cache assigned and use this
+    to automatically reject outdated cache material.  Individual bytecode
+    cache subclasses don't have to care about cache invalidation.
+    """
+
+    def __init__(self, environment: "Environment", key: str, checksum: str) -> None:
+        self.environment = environment
+        self.key = key
+        self.checksum = checksum
+        self.reset()
+
+    def reset(self) -> None:
+        """Resets the bucket (unloads the bytecode)."""
+        self.code: t.Optional[CodeType] = None
+
+    def load_bytecode(self, f: t.BinaryIO) -> None:
+        """Loads bytecode from a file or file like object."""
+        # make sure the magic header is correct
+        magic = f.read(len(bc_magic))
+        if magic != bc_magic:
+            self.reset()
+            return
+        # the source code of the file changed, we need to reload
+        checksum = pickle.load(f)
+        if self.checksum != checksum:
+            self.reset()
+            return
+        # if marshal_load fails then we need to reload
+        try:
+            self.code = marshal.load(f)
+        except (EOFError, ValueError, TypeError):
+            self.reset()
+            return
+
+    def write_bytecode(self, f: t.BinaryIO) -> None:
+        """Dump the bytecode into the file or file like object passed."""
+        if self.code is None:
+            raise TypeError("can't write empty bucket")
+        f.write(bc_magic)
+        pickle.dump(self.checksum, f, 2)
+        marshal.dump(self.code, f)
+
+    def bytecode_from_string(self, string: bytes) -> None:
+        """Load bytecode from bytes."""
+        self.load_bytecode(BytesIO(string))
+
+    def bytecode_to_string(self) -> bytes:
+        """Return the bytecode as bytes."""
+        out = BytesIO()
+        self.write_bytecode(out)
+        return out.getvalue()
+
+
+class BytecodeCache:
+    """To implement your own bytecode cache you have to subclass this class
+    and override :meth:`load_bytecode` and :meth:`dump_bytecode`.  Both of
+    these methods are passed a :class:`~jinja2.bccache.Bucket`.
+
+    A very basic bytecode cache that saves the bytecode on the file system::
+
+        from os import path
+
+        class MyCache(BytecodeCache):
+
+            def __init__(self, directory):
+                self.directory = directory
+
+            def load_bytecode(self, bucket):
+                filename = path.join(self.directory, bucket.key)
+                if path.exists(filename):
+                    with open(filename, 'rb') as f:
+                        bucket.load_bytecode(f)
+
+            def dump_bytecode(self, bucket):
+                filename = path.join(self.directory, bucket.key)
+                with open(filename, 'wb') as f:
+                    bucket.write_bytecode(f)
+
+    A more advanced version of a filesystem based bytecode cache is part of
+    Jinja.
+    """
+
+    def load_bytecode(self, bucket: Bucket) -> None:
+        """Subclasses have to override this method to load bytecode into a
+        bucket.  If they are not able to find code in the cache for the
+        bucket, it must not do anything.
+        """
+        raise NotImplementedError()
+
+    def dump_bytecode(self, bucket: Bucket) -> None:
+        """Subclasses have to override this method to write the bytecode
+        from a bucket back to the cache.  If it unable to do so it must not
+        fail silently but raise an exception.
+        """
+        raise NotImplementedError()
+
+    def clear(self) -> None:
+        """Clears the cache.  This method is not used by Jinja but should be
+        implemented to allow applications to clear the bytecode cache used
+        by a particular environment.
+        """
+
+    def get_cache_key(
+        self, name: str, filename: t.Optional[t.Union[str]] = None
+    ) -> str:
+        """Returns the unique hash key for this template name."""
+        hash = sha1(name.encode("utf-8"))
+
+        if filename is not None:
+            hash.update(f"|{filename}".encode())
+
+        return hash.hexdigest()
+
+    def get_source_checksum(self, source: str) -> str:
+        """Returns a checksum for the source."""
+        return sha1(source.encode("utf-8")).hexdigest()
+
+    def get_bucket(
+        self,
+        environment: "Environment",
+        name: str,
+        filename: t.Optional[str],
+        source: str,
+    ) -> Bucket:
+        """Return a cache bucket for the given template.  All arguments are
+        mandatory but filename may be `None`.
+        """
+        key = self.get_cache_key(name, filename)
+        checksum = self.get_source_checksum(source)
+        bucket = Bucket(environment, key, checksum)
+        self.load_bytecode(bucket)
+        return bucket
+
+    def set_bucket(self, bucket: Bucket) -> None:
+        """Put the bucket into the cache."""
+        self.dump_bytecode(bucket)
+
+
+class FileSystemBytecodeCache(BytecodeCache):
+    """A bytecode cache that stores bytecode on the filesystem.  It accepts
+    two arguments: The directory where the cache items are stored and a
+    pattern string that is used to build the filename.
+
+    If no directory is specified a default cache directory is selected.  On
+    Windows the user's temp directory is used, on UNIX systems a directory
+    is created for the user in the system temp directory.
+
+    The pattern can be used to have multiple separate caches operate on the
+    same directory.  The default pattern is ``'__jinja2_%s.cache'``.  ``%s``
+    is replaced with the cache key.
+
+    >>> bcc = FileSystemBytecodeCache('/tmp/jinja_cache', '%s.cache')
+
+    This bytecode cache supports clearing of the cache using the clear method.
+    """
+
+    def __init__(
+        self, directory: t.Optional[str] = None, pattern: str = "__jinja2_%s.cache"
+    ) -> None:
+        if directory is None:
+            directory = self._get_default_cache_dir()
+        self.directory = directory
+        self.pattern = pattern
+
+    def _get_default_cache_dir(self) -> str:
+        def _unsafe_dir() -> "te.NoReturn":
+            raise RuntimeError(
+                "Cannot determine safe temp directory.  You "
+                "need to explicitly provide one."
+            )
+
+        tmpdir = tempfile.gettempdir()
+
+        # On windows the temporary directory is used specific unless
+        # explicitly forced otherwise.  We can just use that.
+        if os.name == "nt":
+            return tmpdir
+        if not hasattr(os, "getuid"):
+            _unsafe_dir()
+
+        dirname = f"_jinja2-cache-{os.getuid()}"
+        actual_dir = os.path.join(tmpdir, dirname)
+
+        try:
+            os.mkdir(actual_dir, stat.S_IRWXU)
+        except OSError as e:
+            if e.errno != errno.EEXIST:
+                raise
+        try:
+            os.chmod(actual_dir, stat.S_IRWXU)
+            actual_dir_stat = os.lstat(actual_dir)
+            if (
+                actual_dir_stat.st_uid != os.getuid()
+                or not stat.S_ISDIR(actual_dir_stat.st_mode)
+                or stat.S_IMODE(actual_dir_stat.st_mode) != stat.S_IRWXU
+            ):
+                _unsafe_dir()
+        except OSError as e:
+            if e.errno != errno.EEXIST:
+                raise
+
+        actual_dir_stat = os.lstat(actual_dir)
+        if (
+            actual_dir_stat.st_uid != os.getuid()
+            or not stat.S_ISDIR(actual_dir_stat.st_mode)
+            or stat.S_IMODE(actual_dir_stat.st_mode) != stat.S_IRWXU
+        ):
+            _unsafe_dir()
+
+        return actual_dir
+
+    def _get_cache_filename(self, bucket: Bucket) -> str:
+        return os.path.join(self.directory, self.pattern % (bucket.key,))
+
+    def load_bytecode(self, bucket: Bucket) -> None:
+        filename = self._get_cache_filename(bucket)
+
+        if os.path.exists(filename):
+            with open(filename, "rb") as f:
+                bucket.load_bytecode(f)
+
+    def dump_bytecode(self, bucket: Bucket) -> None:
+        with open(self._get_cache_filename(bucket), "wb") as f:
+            bucket.write_bytecode(f)
+
+    def clear(self) -> None:
+        # imported lazily here because google app-engine doesn't support
+        # write access on the file system and the function does not exist
+        # normally.
+        from os import remove
+
+        files = fnmatch.filter(os.listdir(self.directory), self.pattern % ("*",))
+        for filename in files:
+            try:
+                remove(os.path.join(self.directory, filename))
+            except OSError:
+                pass
+
+
+class MemcachedBytecodeCache(BytecodeCache):
+    """This class implements a bytecode cache that uses a memcache cache for
+    storing the information.  It does not enforce a specific memcache library
+    (tummy's memcache or cmemcache) but will accept any class that provides
+    the minimal interface required.
+
+    Libraries compatible with this class:
+
+    -   `cachelib <https://github.com/pallets/cachelib>`_
+    -   `python-memcached <https://pypi.org/project/python-memcached/>`_
+
+    (Unfortunately the django cache interface is not compatible because it
+    does not support storing binary data, only text. You can however pass
+    the underlying cache client to the bytecode cache which is available
+    as `django.core.cache.cache._client`.)
+
+    The minimal interface for the client passed to the constructor is this:
+
+    .. class:: MinimalClientInterface
+
+        .. method:: set(key, value[, timeout])
+
+            Stores the bytecode in the cache.  `value` is a string and
+            `timeout` the timeout of the key.  If timeout is not provided
+            a default timeout or no timeout should be assumed, if it's
+            provided it's an integer with the number of seconds the cache
+            item should exist.
+
+        .. method:: get(key)
+
+            Returns the value for the cache key.  If the item does not
+            exist in the cache the return value must be `None`.
+
+    The other arguments to the constructor are the prefix for all keys that
+    is added before the actual cache key and the timeout for the bytecode in
+    the cache system.  We recommend a high (or no) timeout.
+
+    This bytecode cache does not support clearing of used items in the cache.
+    The clear method is a no-operation function.
+
+    .. versionadded:: 2.7
+       Added support for ignoring memcache errors through the
+       `ignore_memcache_errors` parameter.
+    """
+
+    def __init__(
+        self,
+        client: "_MemcachedClient",
+        prefix: str = "jinja2/bytecode/",
+        timeout: t.Optional[int] = None,
+        ignore_memcache_errors: bool = True,
+    ):
+        self.client = client
+        self.prefix = prefix
+        self.timeout = timeout
+        self.ignore_memcache_errors = ignore_memcache_errors
+
+    def load_bytecode(self, bucket: Bucket) -> None:
+        try:
+            code = self.client.get(self.prefix + bucket.key)
+        except Exception:
+            if not self.ignore_memcache_errors:
+                raise
+        else:
+            bucket.bytecode_from_string(code)
+
+    def dump_bytecode(self, bucket: Bucket) -> None:
+        key = self.prefix + bucket.key
+        value = bucket.bytecode_to_string()
+
+        try:
+            if self.timeout is not None:
+                self.client.set(key, value, self.timeout)
+            else:
+                self.client.set(key, value)
+        except Exception:
+            if not self.ignore_memcache_errors:
+                raise

lib/spack/external/_vendoring/jinja2/constants.py

@@ -0,0 +1,20 @@
+#: list of lorem ipsum words used by the lipsum() helper function
+LOREM_IPSUM_WORDS = """\
+a ac accumsan ad adipiscing aenean aliquam aliquet amet ante aptent arcu at
+auctor augue bibendum blandit class commodo condimentum congue consectetuer
+consequat conubia convallis cras cubilia cum curabitur curae cursus dapibus
+diam dictum dictumst dignissim dis dolor donec dui duis egestas eget eleifend
+elementum elit enim erat eros est et etiam eu euismod facilisi facilisis fames
+faucibus felis fermentum feugiat fringilla fusce gravida habitant habitasse hac
+hendrerit hymenaeos iaculis id imperdiet in inceptos integer interdum ipsum
+justo lacinia lacus laoreet lectus leo libero ligula litora lobortis lorem
+luctus maecenas magna magnis malesuada massa mattis mauris metus mi molestie
+mollis montes morbi mus nam nascetur natoque nec neque netus nibh nisi nisl non
+nonummy nostra nulla nullam nunc odio orci ornare parturient pede pellentesque
+penatibus per pharetra phasellus placerat platea porta porttitor posuere
+potenti praesent pretium primis proin pulvinar purus quam quis quisque rhoncus
+ridiculus risus rutrum sagittis sapien scelerisque sed sem semper senectus sit
+sociis sociosqu sodales sollicitudin suscipit suspendisse taciti tellus tempor
+tempus tincidunt torquent tortor tristique turpis ullamcorper ultrices
+ultricies urna ut varius vehicula vel velit venenatis vestibulum vitae vivamus
+viverra volutpat vulputate"""

lib/spack/external/_vendoring/jinja2/debug.py

@@ -0,0 +1,259 @@
+import platform
+import sys
+import typing as t
+from types import CodeType
+from types import TracebackType
+
+from .exceptions import TemplateSyntaxError
+from .utils import internal_code
+from .utils import missing
+
+if t.TYPE_CHECKING:
+    from .runtime import Context
+
+
+def rewrite_traceback_stack(source: t.Optional[str] = None) -> BaseException:
+    """Rewrite the current exception to replace any tracebacks from
+    within compiled template code with tracebacks that look like they
+    came from the template source.
+
+    This must be called within an ``except`` block.
+
+    :param source: For ``TemplateSyntaxError``, the original source if
+        known.
+    :return: The original exception with the rewritten traceback.
+    """
+    _, exc_value, tb = sys.exc_info()
+    exc_value = t.cast(BaseException, exc_value)
+    tb = t.cast(TracebackType, tb)
+
+    if isinstance(exc_value, TemplateSyntaxError) and not exc_value.translated:
+        exc_value.translated = True
+        exc_value.source = source
+        # Remove the old traceback, otherwise the frames from the
+        # compiler still show up.
+        exc_value.with_traceback(None)
+        # Outside of runtime, so the frame isn't executing template
+        # code, but it still needs to point at the template.
+        tb = fake_traceback(
+            exc_value, None, exc_value.filename or "<unknown>", exc_value.lineno
+        )
+    else:
+        # Skip the frame for the render function.
+        tb = tb.tb_next
+
+    stack = []
+
+    # Build the stack of traceback object, replacing any in template
+    # code with the source file and line information.
+    while tb is not None:
+        # Skip frames decorated with @internalcode. These are internal
+        # calls that aren't useful in template debugging output.
+        if tb.tb_frame.f_code in internal_code:
+            tb = tb.tb_next
+            continue
+
+        template = tb.tb_frame.f_globals.get("__jinja_template__")
+
+        if template is not None:
+            lineno = template.get_corresponding_lineno(tb.tb_lineno)
+            fake_tb = fake_traceback(exc_value, tb, template.filename, lineno)
+            stack.append(fake_tb)
+        else:
+            stack.append(tb)
+
+        tb = tb.tb_next
+
+    tb_next = None
+
+    # Assign tb_next in reverse to avoid circular references.
+    for tb in reversed(stack):
+        tb_next = tb_set_next(tb, tb_next)
+
+    return exc_value.with_traceback(tb_next)
+
+
+def fake_traceback(  # type: ignore
+    exc_value: BaseException, tb: t.Optional[TracebackType], filename: str, lineno: int
+) -> TracebackType:
+    """Produce a new traceback object that looks like it came from the
+    template source instead of the compiled code. The filename, line
+    number, and location name will point to the template, and the local
+    variables will be the current template context.
+
+    :param exc_value: The original exception to be re-raised to create
+        the new traceback.
+    :param tb: The original traceback to get the local variables and
+        code info from.
+    :param filename: The template filename.
+    :param lineno: The line number in the template source.
+    """
+    if tb is not None:
+        # Replace the real locals with the context that would be
+        # available at that point in the template.
+        locals = get_template_locals(tb.tb_frame.f_locals)
+        locals.pop("__jinja_exception__", None)
+    else:
+        locals = {}
+
+    globals = {
+        "__name__": filename,
+        "__file__": filename,
+        "__jinja_exception__": exc_value,
+    }
+    # Raise an exception at the correct line number.
+    code: CodeType = compile(
+        "\n" * (lineno - 1) + "raise __jinja_exception__", filename, "exec"
+    )
+
+    # Build a new code object that points to the template file and
+    # replaces the location with a block name.
+    location = "template"
+
+    if tb is not None:
+        function = tb.tb_frame.f_code.co_name
+
+        if function == "root":
+            location = "top-level template code"
+        elif function.startswith("block_"):
+            location = f"block {function[6:]!r}"
+
+    if sys.version_info >= (3, 8):
+        code = code.replace(co_name=location)
+    else:
+        code = CodeType(
+            code.co_argcount,
+            code.co_kwonlyargcount,
+            code.co_nlocals,
+            code.co_stacksize,
+            code.co_flags,
+            code.co_code,
+            code.co_consts,
+            code.co_names,
+            code.co_varnames,
+            code.co_filename,
+            location,
+            code.co_firstlineno,
+            code.co_lnotab,
+            code.co_freevars,
+            code.co_cellvars,
+        )
+
+    # Execute the new code, which is guaranteed to raise, and return
+    # the new traceback without this frame.
+    try:
+        exec(code, globals, locals)
+    except BaseException:
+        return sys.exc_info()[2].tb_next  # type: ignore
+
+
+def get_template_locals(real_locals: t.Mapping[str, t.Any]) -> t.Dict[str, t.Any]:
+    """Based on the runtime locals, get the context that would be
+    available at that point in the template.
+    """
+    # Start with the current template context.
+    ctx: "t.Optional[Context]" = real_locals.get("context")
+
+    if ctx is not None:
+        data: t.Dict[str, t.Any] = ctx.get_all().copy()
+    else:
+        data = {}
+
+    # Might be in a derived context that only sets local variables
+    # rather than pushing a context. Local variables follow the scheme
+    # l_depth_name. Find the highest-depth local that has a value for
+    # each name.
+    local_overrides: t.Dict[str, t.Tuple[int, t.Any]] = {}
+
+    for name, value in real_locals.items():
+        if not name.startswith("l_") or value is missing:
+            # Not a template variable, or no longer relevant.
+            continue
+
+        try:
+            _, depth_str, name = name.split("_", 2)
+            depth = int(depth_str)
+        except ValueError:
+            continue
+
+        cur_depth = local_overrides.get(name, (-1,))[0]
+
+        if cur_depth < depth:
+            local_overrides[name] = (depth, value)
+
+    # Modify the context with any derived context.
+    for name, (_, value) in local_overrides.items():
+        if value is missing:
+            data.pop(name, None)
+        else:
+            data[name] = value
+
+    return data
+
+
+if sys.version_info >= (3, 7):
+    # tb_next is directly assignable as of Python 3.7
+    def tb_set_next(
+        tb: TracebackType, tb_next: t.Optional[TracebackType]
+    ) -> TracebackType:
+        tb.tb_next = tb_next
+        return tb
+
+
+elif platform.python_implementation() == "PyPy":
+    # PyPy might have special support, and won't work with ctypes.
+    try:
+        import tputil  # type: ignore
+    except ImportError:
+        # Without tproxy support, use the original traceback.
+        def tb_set_next(
+            tb: TracebackType, tb_next: t.Optional[TracebackType]
+        ) -> TracebackType:
+            return tb
+
+    else:
+        # With tproxy support, create a proxy around the traceback that
+        # returns the new tb_next.
+        def tb_set_next(
+            tb: TracebackType, tb_next: t.Optional[TracebackType]
+        ) -> TracebackType:
+            def controller(op):  # type: ignore
+                if op.opname == "__getattribute__" and op.args[0] == "tb_next":
+                    return tb_next
+
+                return op.delegate()
+
+            return tputil.make_proxy(controller, obj=tb)  # type: ignore
+
+
+else:
+    # Use ctypes to assign tb_next at the C level since it's read-only
+    # from Python.
+    import ctypes
+
+    class _CTraceback(ctypes.Structure):
+        _fields_ = [
+            # Extra PyObject slots when compiled with Py_TRACE_REFS.
+            ("PyObject_HEAD", ctypes.c_byte * object().__sizeof__()),
+            # Only care about tb_next as an object, not a traceback.
+            ("tb_next", ctypes.py_object),
+        ]
+
+    def tb_set_next(
+        tb: TracebackType, tb_next: t.Optional[TracebackType]
+    ) -> TracebackType:
+        c_tb = _CTraceback.from_address(id(tb))
+
+        # Clear out the old tb_next.
+        if tb.tb_next is not None:
+            c_tb_next = ctypes.py_object(tb.tb_next)
+            c_tb.tb_next = ctypes.py_object()
+            ctypes.pythonapi.Py_DecRef(c_tb_next)
+
+        # Assign the new tb_next.
+        if tb_next is not None:
+            c_tb_next = ctypes.py_object(tb_next)
+            ctypes.pythonapi.Py_IncRef(c_tb_next)
+            c_tb.tb_next = c_tb_next
+
+        return tb

lib/spack/external/_vendoring/jinja2/defaults.py

@@ -0,0 +1,48 @@
+import typing as t
+
+from .filters import FILTERS as DEFAULT_FILTERS  # noqa: F401
+from .tests import TESTS as DEFAULT_TESTS  # noqa: F401
+from .utils import Cycler
+from .utils import generate_lorem_ipsum
+from .utils import Joiner
+from .utils import Namespace
+
+if t.TYPE_CHECKING:
+    import typing_extensions as te
+
+# defaults for the parser / lexer
+BLOCK_START_STRING = "{%"
+BLOCK_END_STRING = "%}"
+VARIABLE_START_STRING = "{{"
+VARIABLE_END_STRING = "}}"
+COMMENT_START_STRING = "{#"
+COMMENT_END_STRING = "#}"
+LINE_STATEMENT_PREFIX: t.Optional[str] = None
+LINE_COMMENT_PREFIX: t.Optional[str] = None
+TRIM_BLOCKS = False
+LSTRIP_BLOCKS = False
+NEWLINE_SEQUENCE: "te.Literal['\\n', '\\r\\n', '\\r']" = "\n"
+KEEP_TRAILING_NEWLINE = False
+
+# default filters, tests and namespace
+
+DEFAULT_NAMESPACE = {
+    "range": range,
+    "dict": dict,
+    "lipsum": generate_lorem_ipsum,
+    "cycler": Cycler,
+    "joiner": Joiner,
+    "namespace": Namespace,
+}
+
+# default policies
+DEFAULT_POLICIES: t.Dict[str, t.Any] = {
+    "compiler.ascii_str": True,
+    "urlize.rel": "noopener",
+    "urlize.target": None,
+    "urlize.extra_schemes": None,
+    "truncate.leeway": 5,
+    "json.dumps_function": None,
+    "json.dumps_kwargs": {"sort_keys": True},
+    "ext.i18n.trimmed": False,
+}

lib/spack/external/_vendoring/jinja2/exceptions.py

@@ -0,0 +1,166 @@
+import typing as t
+
+if t.TYPE_CHECKING:
+    from .runtime import Undefined
+
+
+class TemplateError(Exception):
+    """Baseclass for all template errors."""
+
+    def __init__(self, message: t.Optional[str] = None) -> None:
+        super().__init__(message)
+
+    @property
+    def message(self) -> t.Optional[str]:
+        return self.args[0] if self.args else None
+
+
+class TemplateNotFound(IOError, LookupError, TemplateError):
+    """Raised if a template does not exist.
+
+    .. versionchanged:: 2.11
+        If the given name is :class:`Undefined` and no message was
+        provided, an :exc:`UndefinedError` is raised.
+    """
+
+    # Silence the Python warning about message being deprecated since
+    # it's not valid here.
+    message: t.Optional[str] = None
+
+    def __init__(
+        self,
+        name: t.Optional[t.Union[str, "Undefined"]],
+        message: t.Optional[str] = None,
+    ) -> None:
+        IOError.__init__(self, name)
+
+        if message is None:
+            from .runtime import Undefined
+
+            if isinstance(name, Undefined):
+                name._fail_with_undefined_error()
+
+            message = name
+
+        self.message = message
+        self.name = name
+        self.templates = [name]
+
+    def __str__(self) -> str:
+        return str(self.message)
+
+
+class TemplatesNotFound(TemplateNotFound):
+    """Like :class:`TemplateNotFound` but raised if multiple templates
+    are selected.  This is a subclass of :class:`TemplateNotFound`
+    exception, so just catching the base exception will catch both.
+
+    .. versionchanged:: 2.11
+        If a name in the list of names is :class:`Undefined`, a message
+        about it being undefined is shown rather than the empty string.
+
+    .. versionadded:: 2.2
+    """
+
+    def __init__(
+        self,
+        names: t.Sequence[t.Union[str, "Undefined"]] = (),
+        message: t.Optional[str] = None,
+    ) -> None:
+        if message is None:
+            from .runtime import Undefined
+
+            parts = []
+
+            for name in names:
+                if isinstance(name, Undefined):
+                    parts.append(name._undefined_message)
+                else:
+                    parts.append(name)
+
+            parts_str = ", ".join(map(str, parts))
+            message = f"none of the templates given were found: {parts_str}"
+
+        super().__init__(names[-1] if names else None, message)
+        self.templates = list(names)
+
+
+class TemplateSyntaxError(TemplateError):
+    """Raised to tell the user that there is a problem with the template."""
+
+    def __init__(
+        self,
+        message: str,
+        lineno: int,
+        name: t.Optional[str] = None,
+        filename: t.Optional[str] = None,
+    ) -> None:
+        super().__init__(message)
+        self.lineno = lineno
+        self.name = name
+        self.filename = filename
+        self.source: t.Optional[str] = None
+
+        # this is set to True if the debug.translate_syntax_error
+        # function translated the syntax error into a new traceback
+        self.translated = False
+
+    def __str__(self) -> str:
+        # for translated errors we only return the message
+        if self.translated:
+            return t.cast(str, self.message)
+
+        # otherwise attach some stuff
+        location = f"line {self.lineno}"
+        name = self.filename or self.name
+        if name:
+            location = f'File "{name}", {location}'
+        lines = [t.cast(str, self.message), "  " + location]
+
+        # if the source is set, add the line to the output
+        if self.source is not None:
+            try:
+                line = self.source.splitlines()[self.lineno - 1]
+            except IndexError:
+                pass
+            else:
+                lines.append("    " + line.strip())
+
+        return "\n".join(lines)
+
+    def __reduce__(self):  # type: ignore
+        # https://bugs.python.org/issue1692335 Exceptions that take
+        # multiple required arguments have problems with pickling.
+        # Without this, raises TypeError: __init__() missing 1 required
+        # positional argument: 'lineno'
+        return self.__class__, (self.message, self.lineno, self.name, self.filename)
+
+
+class TemplateAssertionError(TemplateSyntaxError):
+    """Like a template syntax error, but covers cases where something in the
+    template caused an error at compile time that wasn't necessarily caused
+    by a syntax error.  However it's a direct subclass of
+    :exc:`TemplateSyntaxError` and has the same attributes.
+    """
+
+
+class TemplateRuntimeError(TemplateError):
+    """A generic runtime error in the template engine.  Under some situations
+    Jinja may raise this exception.
+    """
+
+
+class UndefinedError(TemplateRuntimeError):
+    """Raised if a template tries to operate on :class:`Undefined`."""
+
+
+class SecurityError(TemplateRuntimeError):
+    """Raised if a template tries to do something insecure if the
+    sandbox is enabled.
+    """
+
+
+class FilterArgumentError(TemplateRuntimeError):
+    """This error is raised if a filter was called with inappropriate
+    arguments
+    """

lib/spack/external/_vendoring/jinja2/ext.py

@@ -0,0 +1,879 @@
+"""Extension API for adding custom tags and behavior."""
+import pprint
+import re
+import typing as t
+import warnings
+
+from markupsafe import Markup
+
+from . import defaults
+from . import nodes
+from .environment import Environment
+from .exceptions import TemplateAssertionError
+from .exceptions import TemplateSyntaxError
+from .runtime import concat  # type: ignore
+from .runtime import Context
+from .runtime import Undefined
+from .utils import import_string
+from .utils import pass_context
+
+if t.TYPE_CHECKING:
+    import typing_extensions as te
+    from .lexer import Token
+    from .lexer import TokenStream
+    from .parser import Parser
+
+    class _TranslationsBasic(te.Protocol):
+        def gettext(self, message: str) -> str:
+            ...
+
+        def ngettext(self, singular: str, plural: str, n: int) -> str:
+            pass
+
+    class _TranslationsContext(_TranslationsBasic):
+        def pgettext(self, context: str, message: str) -> str:
+            ...
+
+        def npgettext(self, context: str, singular: str, plural: str, n: int) -> str:
+            ...
+
+    _SupportedTranslations = t.Union[_TranslationsBasic, _TranslationsContext]
+
+
+# I18N functions available in Jinja templates. If the I18N library
+# provides ugettext, it will be assigned to gettext.
+GETTEXT_FUNCTIONS: t.Tuple[str, ...] = (
+    "_",
+    "gettext",
+    "ngettext",
+    "pgettext",
+    "npgettext",
+)
+_ws_re = re.compile(r"\s*\n\s*")
+
+
+class Extension:
+    """Extensions can be used to add extra functionality to the Jinja template
+    system at the parser level.  Custom extensions are bound to an environment
+    but may not store environment specific data on `self`.  The reason for
+    this is that an extension can be bound to another environment (for
+    overlays) by creating a copy and reassigning the `environment` attribute.
+
+    As extensions are created by the environment they cannot accept any
+    arguments for configuration.  One may want to work around that by using
+    a factory function, but that is not possible as extensions are identified
+    by their import name.  The correct way to configure the extension is
+    storing the configuration values on the environment.  Because this way the
+    environment ends up acting as central configuration storage the
+    attributes may clash which is why extensions have to ensure that the names
+    they choose for configuration are not too generic.  ``prefix`` for example
+    is a terrible name, ``fragment_cache_prefix`` on the other hand is a good
+    name as includes the name of the extension (fragment cache).
+    """
+
+    identifier: t.ClassVar[str]
+
+    def __init_subclass__(cls) -> None:
+        cls.identifier = f"{cls.__module__}.{cls.__name__}"
+
+    #: if this extension parses this is the list of tags it's listening to.
+    tags: t.Set[str] = set()
+
+    #: the priority of that extension.  This is especially useful for
+    #: extensions that preprocess values.  A lower value means higher
+    #: priority.
+    #:
+    #: .. versionadded:: 2.4
+    priority = 100
+
+    def __init__(self, environment: Environment) -> None:
+        self.environment = environment
+
+    def bind(self, environment: Environment) -> "Extension":
+        """Create a copy of this extension bound to another environment."""
+        rv = t.cast(Extension, object.__new__(self.__class__))
+        rv.__dict__.update(self.__dict__)
+        rv.environment = environment
+        return rv
+
+    def preprocess(
+        self, source: str, name: t.Optional[str], filename: t.Optional[str] = None
+    ) -> str:
+        """This method is called before the actual lexing and can be used to
+        preprocess the source.  The `filename` is optional.  The return value
+        must be the preprocessed source.
+        """
+        return source
+
+    def filter_stream(
+        self, stream: "TokenStream"
+    ) -> t.Union["TokenStream", t.Iterable["Token"]]:
+        """It's passed a :class:`~jinja2.lexer.TokenStream` that can be used
+        to filter tokens returned.  This method has to return an iterable of
+        :class:`~jinja2.lexer.Token`\\s, but it doesn't have to return a
+        :class:`~jinja2.lexer.TokenStream`.
+        """
+        return stream
+
+    def parse(self, parser: "Parser") -> t.Union[nodes.Node, t.List[nodes.Node]]:
+        """If any of the :attr:`tags` matched this method is called with the
+        parser as first argument.  The token the parser stream is pointing at
+        is the name token that matched.  This method has to return one or a
+        list of multiple nodes.
+        """
+        raise NotImplementedError()
+
+    def attr(
+        self, name: str, lineno: t.Optional[int] = None
+    ) -> nodes.ExtensionAttribute:
+        """Return an attribute node for the current extension.  This is useful
+        to pass constants on extensions to generated template code.
+
+        ::
+
+            self.attr('_my_attribute', lineno=lineno)
+        """
+        return nodes.ExtensionAttribute(self.identifier, name, lineno=lineno)
+
+    def call_method(
+        self,
+        name: str,
+        args: t.Optional[t.List[nodes.Expr]] = None,
+        kwargs: t.Optional[t.List[nodes.Keyword]] = None,
+        dyn_args: t.Optional[nodes.Expr] = None,
+        dyn_kwargs: t.Optional[nodes.Expr] = None,
+        lineno: t.Optional[int] = None,
+    ) -> nodes.Call:
+        """Call a method of the extension.  This is a shortcut for
+        :meth:`attr` + :class:`jinja2.nodes.Call`.
+        """
+        if args is None:
+            args = []
+        if kwargs is None:
+            kwargs = []
+        return nodes.Call(
+            self.attr(name, lineno=lineno),
+            args,
+            kwargs,
+            dyn_args,
+            dyn_kwargs,
+            lineno=lineno,
+        )
+
+
+@pass_context
+def _gettext_alias(
+    __context: Context, *args: t.Any, **kwargs: t.Any
+) -> t.Union[t.Any, Undefined]:
+    return __context.call(__context.resolve("gettext"), *args, **kwargs)
+
+
+def _make_new_gettext(func: t.Callable[[str], str]) -> t.Callable[..., str]:
+    @pass_context
+    def gettext(__context: Context, __string: str, **variables: t.Any) -> str:
+        rv = __context.call(func, __string)
+        if __context.eval_ctx.autoescape:
+            rv = Markup(rv)
+        # Always treat as a format string, even if there are no
+        # variables. This makes translation strings more consistent
+        # and predictable. This requires escaping
+        return rv % variables  # type: ignore
+
+    return gettext
+
+
+def _make_new_ngettext(func: t.Callable[[str, str, int], str]) -> t.Callable[..., str]:
+    @pass_context
+    def ngettext(
+        __context: Context,
+        __singular: str,
+        __plural: str,
+        __num: int,
+        **variables: t.Any,
+    ) -> str:
+        variables.setdefault("num", __num)
+        rv = __context.call(func, __singular, __plural, __num)
+        if __context.eval_ctx.autoescape:
+            rv = Markup(rv)
+        # Always treat as a format string, see gettext comment above.
+        return rv % variables  # type: ignore
+
+    return ngettext
+
+
+def _make_new_pgettext(func: t.Callable[[str, str], str]) -> t.Callable[..., str]:
+    @pass_context
+    def pgettext(
+        __context: Context, __string_ctx: str, __string: str, **variables: t.Any
+    ) -> str:
+        variables.setdefault("context", __string_ctx)
+        rv = __context.call(func, __string_ctx, __string)
+
+        if __context.eval_ctx.autoescape:
+            rv = Markup(rv)
+
+        # Always treat as a format string, see gettext comment above.
+        return rv % variables  # type: ignore
+
+    return pgettext
+
+
+def _make_new_npgettext(
+    func: t.Callable[[str, str, str, int], str]
+) -> t.Callable[..., str]:
+    @pass_context
+    def npgettext(
+        __context: Context,
+        __string_ctx: str,
+        __singular: str,
+        __plural: str,
+        __num: int,
+        **variables: t.Any,
+    ) -> str:
+        variables.setdefault("context", __string_ctx)
+        variables.setdefault("num", __num)
+        rv = __context.call(func, __string_ctx, __singular, __plural, __num)
+
+        if __context.eval_ctx.autoescape:
+            rv = Markup(rv)
+
+        # Always treat as a format string, see gettext comment above.
+        return rv % variables  # type: ignore
+
+    return npgettext
+
+
+class InternationalizationExtension(Extension):
+    """This extension adds gettext support to Jinja."""
+
+    tags = {"trans"}
+
+    # TODO: the i18n extension is currently reevaluating values in a few
+    # situations.  Take this example:
+    #   {% trans count=something() %}{{ count }} foo{% pluralize
+    #     %}{{ count }} fooss{% endtrans %}
+    # something is called twice here.  One time for the gettext value and
+    # the other time for the n-parameter of the ngettext function.
+
+    def __init__(self, environment: Environment) -> None:
+        super().__init__(environment)
+        environment.globals["_"] = _gettext_alias
+        environment.extend(
+            install_gettext_translations=self._install,
+            install_null_translations=self._install_null,
+            install_gettext_callables=self._install_callables,
+            uninstall_gettext_translations=self._uninstall,
+            extract_translations=self._extract,
+            newstyle_gettext=False,
+        )
+
+    def _install(
+        self, translations: "_SupportedTranslations", newstyle: t.Optional[bool] = None
+    ) -> None:
+        # ugettext and ungettext are preferred in case the I18N library
+        # is providing compatibility with older Python versions.
+        gettext = getattr(translations, "ugettext", None)
+        if gettext is None:
+            gettext = translations.gettext
+        ngettext = getattr(translations, "ungettext", None)
+        if ngettext is None:
+            ngettext = translations.ngettext
+
+        pgettext = getattr(translations, "pgettext", None)
+        npgettext = getattr(translations, "npgettext", None)
+        self._install_callables(
+            gettext, ngettext, newstyle=newstyle, pgettext=pgettext, npgettext=npgettext
+        )
+
+    def _install_null(self, newstyle: t.Optional[bool] = None) -> None:
+        import gettext
+
+        translations = gettext.NullTranslations()
+
+        if hasattr(translations, "pgettext"):
+            # Python < 3.8
+            pgettext = translations.pgettext  # type: ignore
+        else:
+
+            def pgettext(c: str, s: str) -> str:
+                return s
+
+        if hasattr(translations, "npgettext"):
+            npgettext = translations.npgettext  # type: ignore
+        else:
+
+            def npgettext(c: str, s: str, p: str, n: int) -> str:
+                return s if n == 1 else p
+
+        self._install_callables(
+            gettext=translations.gettext,
+            ngettext=translations.ngettext,
+            newstyle=newstyle,
+            pgettext=pgettext,
+            npgettext=npgettext,
+        )
+
+    def _install_callables(
+        self,
+        gettext: t.Callable[[str], str],
+        ngettext: t.Callable[[str, str, int], str],
+        newstyle: t.Optional[bool] = None,
+        pgettext: t.Optional[t.Callable[[str, str], str]] = None,
+        npgettext: t.Optional[t.Callable[[str, str, str, int], str]] = None,
+    ) -> None:
+        if newstyle is not None:
+            self.environment.newstyle_gettext = newstyle  # type: ignore
+        if self.environment.newstyle_gettext:  # type: ignore
+            gettext = _make_new_gettext(gettext)
+            ngettext = _make_new_ngettext(ngettext)
+
+            if pgettext is not None:
+                pgettext = _make_new_pgettext(pgettext)
+
+            if npgettext is not None:
+                npgettext = _make_new_npgettext(npgettext)
+
+        self.environment.globals.update(
+            gettext=gettext, ngettext=ngettext, pgettext=pgettext, npgettext=npgettext
+        )
+
+    def _uninstall(self, translations: "_SupportedTranslations") -> None:
+        for key in ("gettext", "ngettext", "pgettext", "npgettext"):
+            self.environment.globals.pop(key, None)
+
+    def _extract(
+        self,
+        source: t.Union[str, nodes.Template],
+        gettext_functions: t.Sequence[str] = GETTEXT_FUNCTIONS,
+    ) -> t.Iterator[
+        t.Tuple[int, str, t.Union[t.Optional[str], t.Tuple[t.Optional[str], ...]]]
+    ]:
+        if isinstance(source, str):
+            source = self.environment.parse(source)
+        return extract_from_ast(source, gettext_functions)
+
+    def parse(self, parser: "Parser") -> t.Union[nodes.Node, t.List[nodes.Node]]:
+        """Parse a translatable tag."""
+        lineno = next(parser.stream).lineno
+        num_called_num = False
+
+        # find all the variables referenced.  Additionally a variable can be
+        # defined in the body of the trans block too, but this is checked at
+        # a later state.
+        plural_expr: t.Optional[nodes.Expr] = None
+        plural_expr_assignment: t.Optional[nodes.Assign] = None
+        variables: t.Dict[str, nodes.Expr] = {}
+        trimmed = None
+        while parser.stream.current.type != "block_end":
+            if variables:
+                parser.stream.expect("comma")
+
+            # skip colon for python compatibility
+            if parser.stream.skip_if("colon"):
+                break
+
+            token = parser.stream.expect("name")
+            if token.value in variables:
+                parser.fail(
+                    f"translatable variable {token.value!r} defined twice.",
+                    token.lineno,
+                    exc=TemplateAssertionError,
+                )
+
+            # expressions
+            if parser.stream.current.type == "assign":
+                next(parser.stream)
+                variables[token.value] = var = parser.parse_expression()
+            elif trimmed is None and token.value in ("trimmed", "notrimmed"):
+                trimmed = token.value == "trimmed"
+                continue
+            else:
+                variables[token.value] = var = nodes.Name(token.value, "load")
+
+            if plural_expr is None:
+                if isinstance(var, nodes.Call):
+                    plural_expr = nodes.Name("_trans", "load")
+                    variables[token.value] = plural_expr
+                    plural_expr_assignment = nodes.Assign(
+                        nodes.Name("_trans", "store"), var
+                    )
+                else:
+                    plural_expr = var
+                num_called_num = token.value == "num"
+
+        parser.stream.expect("block_end")
+
+        plural = None
+        have_plural = False
+        referenced = set()
+
+        # now parse until endtrans or pluralize
+        singular_names, singular = self._parse_block(parser, True)
+        if singular_names:
+            referenced.update(singular_names)
+            if plural_expr is None:
+                plural_expr = nodes.Name(singular_names[0], "load")
+                num_called_num = singular_names[0] == "num"
+
+        # if we have a pluralize block, we parse that too
+        if parser.stream.current.test("name:pluralize"):
+            have_plural = True
+            next(parser.stream)
+            if parser.stream.current.type != "block_end":
+                token = parser.stream.expect("name")
+                if token.value not in variables:
+                    parser.fail(
+                        f"unknown variable {token.value!r} for pluralization",
+                        token.lineno,
+                        exc=TemplateAssertionError,
+                    )
+                plural_expr = variables[token.value]
+                num_called_num = token.value == "num"
+            parser.stream.expect("block_end")
+            plural_names, plural = self._parse_block(parser, False)
+            next(parser.stream)
+            referenced.update(plural_names)
+        else:
+            next(parser.stream)
+
+        # register free names as simple name expressions
+        for name in referenced:
+            if name not in variables:
+                variables[name] = nodes.Name(name, "load")
+
+        if not have_plural:
+            plural_expr = None
+        elif plural_expr is None:
+            parser.fail("pluralize without variables", lineno)
+
+        if trimmed is None:
+            trimmed = self.environment.policies["ext.i18n.trimmed"]
+        if trimmed:
+            singular = self._trim_whitespace(singular)
+            if plural:
+                plural = self._trim_whitespace(plural)
+
+        node = self._make_node(
+            singular,
+            plural,
+            variables,
+            plural_expr,
+            bool(referenced),
+            num_called_num and have_plural,
+        )
+        node.set_lineno(lineno)
+        if plural_expr_assignment is not None:
+            return [plural_expr_assignment, node]
+        else:
+            return node
+
+    def _trim_whitespace(self, string: str, _ws_re: t.Pattern[str] = _ws_re) -> str:
+        return _ws_re.sub(" ", string.strip())
+
+    def _parse_block(
+        self, parser: "Parser", allow_pluralize: bool
+    ) -> t.Tuple[t.List[str], str]:
+        """Parse until the next block tag with a given name."""
+        referenced = []
+        buf = []
+
+        while True:
+            if parser.stream.current.type == "data":
+                buf.append(parser.stream.current.value.replace("%", "%%"))
+                next(parser.stream)
+            elif parser.stream.current.type == "variable_begin":
+                next(parser.stream)
+                name = parser.stream.expect("name").value
+                referenced.append(name)
+                buf.append(f"%({name})s")
+                parser.stream.expect("variable_end")
+            elif parser.stream.current.type == "block_begin":
+                next(parser.stream)
+                if parser.stream.current.test("name:endtrans"):
+                    break
+                elif parser.stream.current.test("name:pluralize"):
+                    if allow_pluralize:
+                        break
+                    parser.fail(
+                        "a translatable section can have only one pluralize section"
+                    )
+                parser.fail(
+                    "control structures in translatable sections are not allowed"
+                )
+            elif parser.stream.eos:
+                parser.fail("unclosed translation block")
+            else:
+                raise RuntimeError("internal parser error")
+
+        return referenced, concat(buf)
+
+    def _make_node(
+        self,
+        singular: str,
+        plural: t.Optional[str],
+        variables: t.Dict[str, nodes.Expr],
+        plural_expr: t.Optional[nodes.Expr],
+        vars_referenced: bool,
+        num_called_num: bool,
+    ) -> nodes.Output:
+        """Generates a useful node from the data provided."""
+        newstyle = self.environment.newstyle_gettext  # type: ignore
+        node: nodes.Expr
+
+        # no variables referenced?  no need to escape for old style
+        # gettext invocations only if there are vars.
+        if not vars_referenced and not newstyle:
+            singular = singular.replace("%%", "%")
+            if plural:
+                plural = plural.replace("%%", "%")
+
+        # singular only:
+        if plural_expr is None:
+            gettext = nodes.Name("gettext", "load")
+            node = nodes.Call(gettext, [nodes.Const(singular)], [], None, None)
+
+        # singular and plural
+        else:
+            ngettext = nodes.Name("ngettext", "load")
+            node = nodes.Call(
+                ngettext,
+                [nodes.Const(singular), nodes.Const(plural), plural_expr],
+                [],
+                None,
+                None,
+            )
+
+        # in case newstyle gettext is used, the method is powerful
+        # enough to handle the variable expansion and autoescape
+        # handling itself
+        if newstyle:
+            for key, value in variables.items():
+                # the function adds that later anyways in case num was
+                # called num, so just skip it.
+                if num_called_num and key == "num":
+                    continue
+                node.kwargs.append(nodes.Keyword(key, value))
+
+        # otherwise do that here
+        else:
+            # mark the return value as safe if we are in an
+            # environment with autoescaping turned on
+            node = nodes.MarkSafeIfAutoescape(node)
+            if variables:
+                node = nodes.Mod(
+                    node,
+                    nodes.Dict(
+                        [
+                            nodes.Pair(nodes.Const(key), value)
+                            for key, value in variables.items()
+                        ]
+                    ),
+                )
+        return nodes.Output([node])
+
+
+class ExprStmtExtension(Extension):
+    """Adds a `do` tag to Jinja that works like the print statement just
+    that it doesn't print the return value.
+    """
+
+    tags = {"do"}
+
+    def parse(self, parser: "Parser") -> nodes.ExprStmt:
+        node = nodes.ExprStmt(lineno=next(parser.stream).lineno)
+        node.node = parser.parse_tuple()
+        return node
+
+
+class LoopControlExtension(Extension):
+    """Adds break and continue to the template engine."""
+
+    tags = {"break", "continue"}
+
+    def parse(self, parser: "Parser") -> t.Union[nodes.Break, nodes.Continue]:
+        token = next(parser.stream)
+        if token.value == "break":
+            return nodes.Break(lineno=token.lineno)
+        return nodes.Continue(lineno=token.lineno)
+
+
+class WithExtension(Extension):
+    def __init__(self, environment: Environment) -> None:
+        super().__init__(environment)
+        warnings.warn(
+            "The 'with' extension is deprecated and will be removed in"
+            " Jinja 3.1. This is built in now.",
+            DeprecationWarning,
+            stacklevel=3,
+        )
+
+
+class AutoEscapeExtension(Extension):
+    def __init__(self, environment: Environment) -> None:
+        super().__init__(environment)
+        warnings.warn(
+            "The 'autoescape' extension is deprecated and will be"
+            " removed in Jinja 3.1. This is built in now.",
+            DeprecationWarning,
+            stacklevel=3,
+        )
+
+
+class DebugExtension(Extension):
+    """A ``{% debug %}`` tag that dumps the available variables,
+    filters, and tests.
+
+    .. code-block:: html+jinja
+
+        <pre>{% debug %}</pre>
+
+    .. code-block:: text
+
+        {'context': {'cycler': <class 'jinja2.utils.Cycler'>,
+                     ...,
+                     'namespace': <class 'jinja2.utils.Namespace'>},
+         'filters': ['abs', 'attr', 'batch', 'capitalize', 'center', 'count', 'd',
+                     ..., 'urlencode', 'urlize', 'wordcount', 'wordwrap', 'xmlattr'],
+         'tests': ['!=', '<', '<=', '==', '>', '>=', 'callable', 'defined',
+                   ..., 'odd', 'sameas', 'sequence', 'string', 'undefined', 'upper']}
+
+    .. versionadded:: 2.11.0
+    """
+
+    tags = {"debug"}
+
+    def parse(self, parser: "Parser") -> nodes.Output:
+        lineno = parser.stream.expect("name:debug").lineno
+        context = nodes.ContextReference()
+        result = self.call_method("_render", [context], lineno=lineno)
+        return nodes.Output([result], lineno=lineno)
+
+    def _render(self, context: Context) -> str:
+        result = {
+            "context": context.get_all(),
+            "filters": sorted(self.environment.filters.keys()),
+            "tests": sorted(self.environment.tests.keys()),
+        }
+
+        # Set the depth since the intent is to show the top few names.
+        return pprint.pformat(result, depth=3, compact=True)
+
+
+def extract_from_ast(
+    ast: nodes.Template,
+    gettext_functions: t.Sequence[str] = GETTEXT_FUNCTIONS,
+    babel_style: bool = True,
+) -> t.Iterator[
+    t.Tuple[int, str, t.Union[t.Optional[str], t.Tuple[t.Optional[str], ...]]]
+]:
+    """Extract localizable strings from the given template node.  Per
+    default this function returns matches in babel style that means non string
+    parameters as well as keyword arguments are returned as `None`.  This
+    allows Babel to figure out what you really meant if you are using
+    gettext functions that allow keyword arguments for placeholder expansion.
+    If you don't want that behavior set the `babel_style` parameter to `False`
+    which causes only strings to be returned and parameters are always stored
+    in tuples.  As a consequence invalid gettext calls (calls without a single
+    string parameter or string parameters after non-string parameters) are
+    skipped.
+
+    This example explains the behavior:
+
+    >>> from jinja2 import Environment
+    >>> env = Environment()
+    >>> node = env.parse('{{ (_("foo"), _(), ngettext("foo", "bar", 42)) }}')
+    >>> list(extract_from_ast(node))
+    [(1, '_', 'foo'), (1, '_', ()), (1, 'ngettext', ('foo', 'bar', None))]
+    >>> list(extract_from_ast(node, babel_style=False))
+    [(1, '_', ('foo',)), (1, 'ngettext', ('foo', 'bar'))]
+
+    For every string found this function yields a ``(lineno, function,
+    message)`` tuple, where:
+
+    * ``lineno`` is the number of the line on which the string was found,
+    * ``function`` is the name of the ``gettext`` function used (if the
+      string was extracted from embedded Python code), and
+    *   ``message`` is the string, or a tuple of strings for functions
+         with multiple string arguments.
+
+    This extraction function operates on the AST and is because of that unable
+    to extract any comments.  For comment support you have to use the babel
+    extraction interface or extract comments yourself.
+    """
+    out: t.Union[t.Optional[str], t.Tuple[t.Optional[str], ...]]
+
+    for node in ast.find_all(nodes.Call):
+        if (
+            not isinstance(node.node, nodes.Name)
+            or node.node.name not in gettext_functions
+        ):
+            continue
+
+        strings: t.List[t.Optional[str]] = []
+
+        for arg in node.args:
+            if isinstance(arg, nodes.Const) and isinstance(arg.value, str):
+                strings.append(arg.value)
+            else:
+                strings.append(None)
+
+        for _ in node.kwargs:
+            strings.append(None)
+        if node.dyn_args is not None:
+            strings.append(None)
+        if node.dyn_kwargs is not None:
+            strings.append(None)
+
+        if not babel_style:
+            out = tuple(x for x in strings if x is not None)
+
+            if not out:
+                continue
+        else:
+            if len(strings) == 1:
+                out = strings[0]
+            else:
+                out = tuple(strings)
+
+        yield node.lineno, node.node.name, out
+
+
+class _CommentFinder:
+    """Helper class to find comments in a token stream.  Can only
+    find comments for gettext calls forwards.  Once the comment
+    from line 4 is found, a comment for line 1 will not return a
+    usable value.
+    """
+
+    def __init__(
+        self, tokens: t.Sequence[t.Tuple[int, str, str]], comment_tags: t.Sequence[str]
+    ) -> None:
+        self.tokens = tokens
+        self.comment_tags = comment_tags
+        self.offset = 0
+        self.last_lineno = 0
+
+    def find_backwards(self, offset: int) -> t.List[str]:
+        try:
+            for _, token_type, token_value in reversed(
+                self.tokens[self.offset : offset]
+            ):
+                if token_type in ("comment", "linecomment"):
+                    try:
+                        prefix, comment = token_value.split(None, 1)
+                    except ValueError:
+                        continue
+                    if prefix in self.comment_tags:
+                        return [comment.rstrip()]
+            return []
+        finally:
+            self.offset = offset
+
+    def find_comments(self, lineno: int) -> t.List[str]:
+        if not self.comment_tags or self.last_lineno > lineno:
+            return []
+        for idx, (token_lineno, _, _) in enumerate(self.tokens[self.offset :]):
+            if token_lineno > lineno:
+                return self.find_backwards(self.offset + idx)
+        return self.find_backwards(len(self.tokens))
+
+
+def babel_extract(
+    fileobj: t.BinaryIO,
+    keywords: t.Sequence[str],
+    comment_tags: t.Sequence[str],
+    options: t.Dict[str, t.Any],
+) -> t.Iterator[
+    t.Tuple[
+        int, str, t.Union[t.Optional[str], t.Tuple[t.Optional[str], ...]], t.List[str]
+    ]
+]:
+    """Babel extraction method for Jinja templates.
+
+    .. versionchanged:: 2.3
+       Basic support for translation comments was added.  If `comment_tags`
+       is now set to a list of keywords for extraction, the extractor will
+       try to find the best preceding comment that begins with one of the
+       keywords.  For best results, make sure to not have more than one
+       gettext call in one line of code and the matching comment in the
+       same line or the line before.
+
+    .. versionchanged:: 2.5.1
+       The `newstyle_gettext` flag can be set to `True` to enable newstyle
+       gettext calls.
+
+    .. versionchanged:: 2.7
+       A `silent` option can now be provided.  If set to `False` template
+       syntax errors are propagated instead of being ignored.
+
+    :param fileobj: the file-like object the messages should be extracted from
+    :param keywords: a list of keywords (i.e. function names) that should be
+                     recognized as translation functions
+    :param comment_tags: a list of translator tags to search for and include
+                         in the results.
+    :param options: a dictionary of additional options (optional)
+    :return: an iterator over ``(lineno, funcname, message, comments)`` tuples.
+             (comments will be empty currently)
+    """
+    extensions: t.Dict[t.Type[Extension], None] = {}
+
+    for extension_name in options.get("extensions", "").split(","):
+        extension_name = extension_name.strip()
+
+        if not extension_name:
+            continue
+
+        extensions[import_string(extension_name)] = None
+
+    if InternationalizationExtension not in extensions:
+        extensions[InternationalizationExtension] = None
+
+    def getbool(options: t.Mapping[str, str], key: str, default: bool = False) -> bool:
+        return options.get(key, str(default)).lower() in {"1", "on", "yes", "true"}
+
+    silent = getbool(options, "silent", True)
+    environment = Environment(
+        options.get("block_start_string", defaults.BLOCK_START_STRING),
+        options.get("block_end_string", defaults.BLOCK_END_STRING),
+        options.get("variable_start_string", defaults.VARIABLE_START_STRING),
+        options.get("variable_end_string", defaults.VARIABLE_END_STRING),
+        options.get("comment_start_string", defaults.COMMENT_START_STRING),
+        options.get("comment_end_string", defaults.COMMENT_END_STRING),
+        options.get("line_statement_prefix") or defaults.LINE_STATEMENT_PREFIX,
+        options.get("line_comment_prefix") or defaults.LINE_COMMENT_PREFIX,
+        getbool(options, "trim_blocks", defaults.TRIM_BLOCKS),
+        getbool(options, "lstrip_blocks", defaults.LSTRIP_BLOCKS),
+        defaults.NEWLINE_SEQUENCE,
+        getbool(options, "keep_trailing_newline", defaults.KEEP_TRAILING_NEWLINE),
+        tuple(extensions),
+        cache_size=0,
+        auto_reload=False,
+    )
+
+    if getbool(options, "trimmed"):
+        environment.policies["ext.i18n.trimmed"] = True
+    if getbool(options, "newstyle_gettext"):
+        environment.newstyle_gettext = True  # type: ignore
+
+    source = fileobj.read().decode(options.get("encoding", "utf-8"))
+    try:
+        node = environment.parse(source)
+        tokens = list(environment.lex(environment.preprocess(source)))
+    except TemplateSyntaxError:
+        if not silent:
+            raise
+        # skip templates with syntax errors
+        return
+
+    finder = _CommentFinder(tokens, comment_tags)
+    for lineno, func, message in extract_from_ast(node, keywords):
+        yield lineno, func, message, finder.find_comments(lineno)
+
+
+#: nicer import names
+i18n = InternationalizationExtension
+do = ExprStmtExtension
+loopcontrols = LoopControlExtension
+with_ = WithExtension
+autoescape = AutoEscapeExtension
+debug = DebugExtension

lib/spack/external/_vendoring/jinja2/idtracking.py

@@ -0,0 +1,318 @@
+import typing as t
+
+from . import nodes
+from .visitor import NodeVisitor
+
+VAR_LOAD_PARAMETER = "param"
+VAR_LOAD_RESOLVE = "resolve"
+VAR_LOAD_ALIAS = "alias"
+VAR_LOAD_UNDEFINED = "undefined"
+
+
+def find_symbols(
+    nodes: t.Iterable[nodes.Node], parent_symbols: t.Optional["Symbols"] = None
+) -> "Symbols":
+    sym = Symbols(parent=parent_symbols)
+    visitor = FrameSymbolVisitor(sym)
+    for node in nodes:
+        visitor.visit(node)
+    return sym
+
+
+def symbols_for_node(
+    node: nodes.Node, parent_symbols: t.Optional["Symbols"] = None
+) -> "Symbols":
+    sym = Symbols(parent=parent_symbols)
+    sym.analyze_node(node)
+    return sym
+
+
+class Symbols:
+    def __init__(
+        self, parent: t.Optional["Symbols"] = None, level: t.Optional[int] = None
+    ) -> None:
+        if level is None:
+            if parent is None:
+                level = 0
+            else:
+                level = parent.level + 1
+
+        self.level: int = level
+        self.parent = parent
+        self.refs: t.Dict[str, str] = {}
+        self.loads: t.Dict[str, t.Any] = {}
+        self.stores: t.Set[str] = set()
+
+    def analyze_node(self, node: nodes.Node, **kwargs: t.Any) -> None:
+        visitor = RootVisitor(self)
+        visitor.visit(node, **kwargs)
+
+    def _define_ref(
+        self, name: str, load: t.Optional[t.Tuple[str, t.Optional[str]]] = None
+    ) -> str:
+        ident = f"l_{self.level}_{name}"
+        self.refs[name] = ident
+        if load is not None:
+            self.loads[ident] = load
+        return ident
+
+    def find_load(self, target: str) -> t.Optional[t.Any]:
+        if target in self.loads:
+            return self.loads[target]
+
+        if self.parent is not None:
+            return self.parent.find_load(target)
+
+        return None
+
+    def find_ref(self, name: str) -> t.Optional[str]:
+        if name in self.refs:
+            return self.refs[name]
+
+        if self.parent is not None:
+            return self.parent.find_ref(name)
+
+        return None
+
+    def ref(self, name: str) -> str:
+        rv = self.find_ref(name)
+        if rv is None:
+            raise AssertionError(
+                "Tried to resolve a name to a reference that was"
+                f" unknown to the frame ({name!r})"
+            )
+        return rv
+
+    def copy(self) -> "Symbols":
+        rv = t.cast(Symbols, object.__new__(self.__class__))
+        rv.__dict__.update(self.__dict__)
+        rv.refs = self.refs.copy()
+        rv.loads = self.loads.copy()
+        rv.stores = self.stores.copy()
+        return rv
+
+    def store(self, name: str) -> None:
+        self.stores.add(name)
+
+        # If we have not see the name referenced yet, we need to figure
+        # out what to set it to.
+        if name not in self.refs:
+            # If there is a parent scope we check if the name has a
+            # reference there.  If it does it means we might have to alias
+            # to a variable there.
+            if self.parent is not None:
+                outer_ref = self.parent.find_ref(name)
+                if outer_ref is not None:
+                    self._define_ref(name, load=(VAR_LOAD_ALIAS, outer_ref))
+                    return
+
+            # Otherwise we can just set it to undefined.
+            self._define_ref(name, load=(VAR_LOAD_UNDEFINED, None))
+
+    def declare_parameter(self, name: str) -> str:
+        self.stores.add(name)
+        return self._define_ref(name, load=(VAR_LOAD_PARAMETER, None))
+
+    def load(self, name: str) -> None:
+        if self.find_ref(name) is None:
+            self._define_ref(name, load=(VAR_LOAD_RESOLVE, name))
+
+    def branch_update(self, branch_symbols: t.Sequence["Symbols"]) -> None:
+        stores: t.Dict[str, int] = {}
+        for branch in branch_symbols:
+            for target in branch.stores:
+                if target in self.stores:
+                    continue
+                stores[target] = stores.get(target, 0) + 1
+
+        for sym in branch_symbols:
+            self.refs.update(sym.refs)
+            self.loads.update(sym.loads)
+            self.stores.update(sym.stores)
+
+        for name, branch_count in stores.items():
+            if branch_count == len(branch_symbols):
+                continue
+
+            target = self.find_ref(name)  # type: ignore
+            assert target is not None, "should not happen"
+
+            if self.parent is not None:
+                outer_target = self.parent.find_ref(name)
+                if outer_target is not None:
+                    self.loads[target] = (VAR_LOAD_ALIAS, outer_target)
+                    continue
+            self.loads[target] = (VAR_LOAD_RESOLVE, name)
+
+    def dump_stores(self) -> t.Dict[str, str]:
+        rv: t.Dict[str, str] = {}
+        node: t.Optional["Symbols"] = self
+
+        while node is not None:
+            for name in sorted(node.stores):
+                if name not in rv:
+                    rv[name] = self.find_ref(name)  # type: ignore
+
+            node = node.parent
+
+        return rv
+
+    def dump_param_targets(self) -> t.Set[str]:
+        rv = set()
+        node: t.Optional["Symbols"] = self
+
+        while node is not None:
+            for target, (instr, _) in self.loads.items():
+                if instr == VAR_LOAD_PARAMETER:
+                    rv.add(target)
+
+            node = node.parent
+
+        return rv
+
+
+class RootVisitor(NodeVisitor):
+    def __init__(self, symbols: "Symbols") -> None:
+        self.sym_visitor = FrameSymbolVisitor(symbols)
+
+    def _simple_visit(self, node: nodes.Node, **kwargs: t.Any) -> None:
+        for child in node.iter_child_nodes():
+            self.sym_visitor.visit(child)
+
+    visit_Template = _simple_visit
+    visit_Block = _simple_visit
+    visit_Macro = _simple_visit
+    visit_FilterBlock = _simple_visit
+    visit_Scope = _simple_visit
+    visit_If = _simple_visit
+    visit_ScopedEvalContextModifier = _simple_visit
+
+    def visit_AssignBlock(self, node: nodes.AssignBlock, **kwargs: t.Any) -> None:
+        for child in node.body:
+            self.sym_visitor.visit(child)
+
+    def visit_CallBlock(self, node: nodes.CallBlock, **kwargs: t.Any) -> None:
+        for child in node.iter_child_nodes(exclude=("call",)):
+            self.sym_visitor.visit(child)
+
+    def visit_OverlayScope(self, node: nodes.OverlayScope, **kwargs: t.Any) -> None:
+        for child in node.body:
+            self.sym_visitor.visit(child)
+
+    def visit_For(
+        self, node: nodes.For, for_branch: str = "body", **kwargs: t.Any
+    ) -> None:
+        if for_branch == "body":
+            self.sym_visitor.visit(node.target, store_as_param=True)
+            branch = node.body
+        elif for_branch == "else":
+            branch = node.else_
+        elif for_branch == "test":
+            self.sym_visitor.visit(node.target, store_as_param=True)
+            if node.test is not None:
+                self.sym_visitor.visit(node.test)
+            return
+        else:
+            raise RuntimeError("Unknown for branch")
+
+        if branch:
+            for item in branch:
+                self.sym_visitor.visit(item)
+
+    def visit_With(self, node: nodes.With, **kwargs: t.Any) -> None:
+        for target in node.targets:
+            self.sym_visitor.visit(target)
+        for child in node.body:
+            self.sym_visitor.visit(child)
+
+    def generic_visit(self, node: nodes.Node, *args: t.Any, **kwargs: t.Any) -> None:
+        raise NotImplementedError(f"Cannot find symbols for {type(node).__name__!r}")
+
+
+class FrameSymbolVisitor(NodeVisitor):
+    """A visitor for `Frame.inspect`."""
+
+    def __init__(self, symbols: "Symbols") -> None:
+        self.symbols = symbols
+
+    def visit_Name(
+        self, node: nodes.Name, store_as_param: bool = False, **kwargs: t.Any
+    ) -> None:
+        """All assignments to names go through this function."""
+        if store_as_param or node.ctx == "param":
+            self.symbols.declare_parameter(node.name)
+        elif node.ctx == "store":
+            self.symbols.store(node.name)
+        elif node.ctx == "load":
+            self.symbols.load(node.name)
+
+    def visit_NSRef(self, node: nodes.NSRef, **kwargs: t.Any) -> None:
+        self.symbols.load(node.name)
+
+    def visit_If(self, node: nodes.If, **kwargs: t.Any) -> None:
+        self.visit(node.test, **kwargs)
+        original_symbols = self.symbols
+
+        def inner_visit(nodes: t.Iterable[nodes.Node]) -> "Symbols":
+            self.symbols = rv = original_symbols.copy()
+
+            for subnode in nodes:
+                self.visit(subnode, **kwargs)
+
+            self.symbols = original_symbols
+            return rv
+
+        body_symbols = inner_visit(node.body)
+        elif_symbols = inner_visit(node.elif_)
+        else_symbols = inner_visit(node.else_ or ())
+        self.symbols.branch_update([body_symbols, elif_symbols, else_symbols])
+
+    def visit_Macro(self, node: nodes.Macro, **kwargs: t.Any) -> None:
+        self.symbols.store(node.name)
+
+    def visit_Import(self, node: nodes.Import, **kwargs: t.Any) -> None:
+        self.generic_visit(node, **kwargs)
+        self.symbols.store(node.target)
+
+    def visit_FromImport(self, node: nodes.FromImport, **kwargs: t.Any) -> None:
+        self.generic_visit(node, **kwargs)
+
+        for name in node.names:
+            if isinstance(name, tuple):
+                self.symbols.store(name[1])
+            else:
+                self.symbols.store(name)
+
+    def visit_Assign(self, node: nodes.Assign, **kwargs: t.Any) -> None:
+        """Visit assignments in the correct order."""
+        self.visit(node.node, **kwargs)
+        self.visit(node.target, **kwargs)
+
+    def visit_For(self, node: nodes.For, **kwargs: t.Any) -> None:
+        """Visiting stops at for blocks.  However the block sequence
+        is visited as part of the outer scope.
+        """
+        self.visit(node.iter, **kwargs)
+
+    def visit_CallBlock(self, node: nodes.CallBlock, **kwargs: t.Any) -> None:
+        self.visit(node.call, **kwargs)
+
+    def visit_FilterBlock(self, node: nodes.FilterBlock, **kwargs: t.Any) -> None:
+        self.visit(node.filter, **kwargs)
+
+    def visit_With(self, node: nodes.With, **kwargs: t.Any) -> None:
+        for target in node.values:
+            self.visit(target)
+
+    def visit_AssignBlock(self, node: nodes.AssignBlock, **kwargs: t.Any) -> None:
+        """Stop visiting at block assigns."""
+        self.visit(node.target, **kwargs)
+
+    def visit_Scope(self, node: nodes.Scope, **kwargs: t.Any) -> None:
+        """Stop visiting at scopes."""
+
+    def visit_Block(self, node: nodes.Block, **kwargs: t.Any) -> None:
+        """Stop visiting at blocks."""
+
+    def visit_OverlayScope(self, node: nodes.OverlayScope, **kwargs: t.Any) -> None:
+        """Do not visit into overlay scopes."""

lib/spack/external/_vendoring/jinja2/lexer.py

@@ -0,0 +1,869 @@
+"""Implements a Jinja / Python combination lexer. The ``Lexer`` class
+is used to do some preprocessing. It filters out invalid operators like
+the bitshift operators we don't allow in templates. It separates
+template code and python code in expressions.
+"""
+import re
+import typing as t
+from ast import literal_eval
+from collections import deque
+from sys import intern
+
+from ._identifier import pattern as name_re
+from .exceptions import TemplateSyntaxError
+from .utils import LRUCache
+
+if t.TYPE_CHECKING:
+    import typing_extensions as te
+    from .environment import Environment
+
+# cache for the lexers. Exists in order to be able to have multiple
+# environments with the same lexer
+_lexer_cache: t.MutableMapping[t.Tuple, "Lexer"] = LRUCache(50)  # type: ignore
+
+# static regular expressions
+whitespace_re = re.compile(r"\s+")
+newline_re = re.compile(r"(\r\n|\r|\n)")
+string_re = re.compile(
+    r"('([^'\\]*(?:\\.[^'\\]*)*)'" r'|"([^"\\]*(?:\\.[^"\\]*)*)")', re.S
+)
+integer_re = re.compile(
+    r"""
+    (
+        0b(_?[0-1])+ # binary
+    |
+        0o(_?[0-7])+ # octal
+    |
+        0x(_?[\da-f])+ # hex
+    |
+        [1-9](_?\d)* # decimal
+    |
+        0(_?0)* # decimal zero
+    )
+    """,
+    re.IGNORECASE | re.VERBOSE,
+)
+float_re = re.compile(
+    r"""
+    (?<!\.)  # doesn't start with a .
+    (\d+_)*\d+  # digits, possibly _ separated
+    (
+        (\.(\d+_)*\d+)?  # optional fractional part
+        e[+\-]?(\d+_)*\d+  # exponent part
+    |
+        \.(\d+_)*\d+  # required fractional part
+    )
+    """,
+    re.IGNORECASE | re.VERBOSE,
+)
+
+# internal the tokens and keep references to them
+TOKEN_ADD = intern("add")
+TOKEN_ASSIGN = intern("assign")
+TOKEN_COLON = intern("colon")
+TOKEN_COMMA = intern("comma")
+TOKEN_DIV = intern("div")
+TOKEN_DOT = intern("dot")
+TOKEN_EQ = intern("eq")
+TOKEN_FLOORDIV = intern("floordiv")
+TOKEN_GT = intern("gt")
+TOKEN_GTEQ = intern("gteq")
+TOKEN_LBRACE = intern("lbrace")
+TOKEN_LBRACKET = intern("lbracket")
+TOKEN_LPAREN = intern("lparen")
+TOKEN_LT = intern("lt")
+TOKEN_LTEQ = intern("lteq")
+TOKEN_MOD = intern("mod")
+TOKEN_MUL = intern("mul")
+TOKEN_NE = intern("ne")
+TOKEN_PIPE = intern("pipe")
+TOKEN_POW = intern("pow")
+TOKEN_RBRACE = intern("rbrace")
+TOKEN_RBRACKET = intern("rbracket")
+TOKEN_RPAREN = intern("rparen")
+TOKEN_SEMICOLON = intern("semicolon")
+TOKEN_SUB = intern("sub")
+TOKEN_TILDE = intern("tilde")
+TOKEN_WHITESPACE = intern("whitespace")
+TOKEN_FLOAT = intern("float")
+TOKEN_INTEGER = intern("integer")
+TOKEN_NAME = intern("name")
+TOKEN_STRING = intern("string")
+TOKEN_OPERATOR = intern("operator")
+TOKEN_BLOCK_BEGIN = intern("block_begin")
+TOKEN_BLOCK_END = intern("block_end")
+TOKEN_VARIABLE_BEGIN = intern("variable_begin")
+TOKEN_VARIABLE_END = intern("variable_end")
+TOKEN_RAW_BEGIN = intern("raw_begin")
+TOKEN_RAW_END = intern("raw_end")
+TOKEN_COMMENT_BEGIN = intern("comment_begin")
+TOKEN_COMMENT_END = intern("comment_end")
+TOKEN_COMMENT = intern("comment")
+TOKEN_LINESTATEMENT_BEGIN = intern("linestatement_begin")
+TOKEN_LINESTATEMENT_END = intern("linestatement_end")
+TOKEN_LINECOMMENT_BEGIN = intern("linecomment_begin")
+TOKEN_LINECOMMENT_END = intern("linecomment_end")
+TOKEN_LINECOMMENT = intern("linecomment")
+TOKEN_DATA = intern("data")
+TOKEN_INITIAL = intern("initial")
+TOKEN_EOF = intern("eof")
+
+# bind operators to token types
+operators = {
+    "+": TOKEN_ADD,
+    "-": TOKEN_SUB,
+    "/": TOKEN_DIV,
+    "//": TOKEN_FLOORDIV,
+    "*": TOKEN_MUL,
+    "%": TOKEN_MOD,
+    "**": TOKEN_POW,
+    "~": TOKEN_TILDE,
+    "[": TOKEN_LBRACKET,
+    "]": TOKEN_RBRACKET,
+    "(": TOKEN_LPAREN,
+    ")": TOKEN_RPAREN,
+    "{": TOKEN_LBRACE,
+    "}": TOKEN_RBRACE,
+    "==": TOKEN_EQ,
+    "!=": TOKEN_NE,
+    ">": TOKEN_GT,
+    ">=": TOKEN_GTEQ,
+    "<": TOKEN_LT,
+    "<=": TOKEN_LTEQ,
+    "=": TOKEN_ASSIGN,
+    ".": TOKEN_DOT,
+    ":": TOKEN_COLON,
+    "|": TOKEN_PIPE,
+    ",": TOKEN_COMMA,
+    ";": TOKEN_SEMICOLON,
+}
+
+reverse_operators = {v: k for k, v in operators.items()}
+assert len(operators) == len(reverse_operators), "operators dropped"
+operator_re = re.compile(
+    f"({'|'.join(re.escape(x) for x in sorted(operators, key=lambda x: -len(x)))})"
+)
+
+ignored_tokens = frozenset(
+    [
+        TOKEN_COMMENT_BEGIN,
+        TOKEN_COMMENT,
+        TOKEN_COMMENT_END,
+        TOKEN_WHITESPACE,
+        TOKEN_LINECOMMENT_BEGIN,
+        TOKEN_LINECOMMENT_END,
+        TOKEN_LINECOMMENT,
+    ]
+)
+ignore_if_empty = frozenset(
+    [TOKEN_WHITESPACE, TOKEN_DATA, TOKEN_COMMENT, TOKEN_LINECOMMENT]
+)
+
+
+def _describe_token_type(token_type: str) -> str:
+    if token_type in reverse_operators:
+        return reverse_operators[token_type]
+
+    return {
+        TOKEN_COMMENT_BEGIN: "begin of comment",
+        TOKEN_COMMENT_END: "end of comment",
+        TOKEN_COMMENT: "comment",
+        TOKEN_LINECOMMENT: "comment",
+        TOKEN_BLOCK_BEGIN: "begin of statement block",
+        TOKEN_BLOCK_END: "end of statement block",
+        TOKEN_VARIABLE_BEGIN: "begin of print statement",
+        TOKEN_VARIABLE_END: "end of print statement",
+        TOKEN_LINESTATEMENT_BEGIN: "begin of line statement",
+        TOKEN_LINESTATEMENT_END: "end of line statement",
+        TOKEN_DATA: "template data / text",
+        TOKEN_EOF: "end of template",
+    }.get(token_type, token_type)
+
+
+def describe_token(token: "Token") -> str:
+    """Returns a description of the token."""
+    if token.type == TOKEN_NAME:
+        return token.value
+
+    return _describe_token_type(token.type)
+
+
+def describe_token_expr(expr: str) -> str:
+    """Like `describe_token` but for token expressions."""
+    if ":" in expr:
+        type, value = expr.split(":", 1)
+
+        if type == TOKEN_NAME:
+            return value
+    else:
+        type = expr
+
+    return _describe_token_type(type)
+
+
+def count_newlines(value: str) -> int:
+    """Count the number of newline characters in the string.  This is
+    useful for extensions that filter a stream.
+    """
+    return len(newline_re.findall(value))
+
+
+def compile_rules(environment: "Environment") -> t.List[t.Tuple[str, str]]:
+    """Compiles all the rules from the environment into a list of rules."""
+    e = re.escape
+    rules = [
+        (
+            len(environment.comment_start_string),
+            TOKEN_COMMENT_BEGIN,
+            e(environment.comment_start_string),
+        ),
+        (
+            len(environment.block_start_string),
+            TOKEN_BLOCK_BEGIN,
+            e(environment.block_start_string),
+        ),
+        (
+            len(environment.variable_start_string),
+            TOKEN_VARIABLE_BEGIN,
+            e(environment.variable_start_string),
+        ),
+    ]
+
+    if environment.line_statement_prefix is not None:
+        rules.append(
+            (
+                len(environment.line_statement_prefix),
+                TOKEN_LINESTATEMENT_BEGIN,
+                r"^[ \t\v]*" + e(environment.line_statement_prefix),
+            )
+        )
+    if environment.line_comment_prefix is not None:
+        rules.append(
+            (
+                len(environment.line_comment_prefix),
+                TOKEN_LINECOMMENT_BEGIN,
+                r"(?:^|(?<=\S))[^\S\r\n]*" + e(environment.line_comment_prefix),
+            )
+        )
+
+    return [x[1:] for x in sorted(rules, reverse=True)]
+
+
+class Failure:
+    """Class that raises a `TemplateSyntaxError` if called.
+    Used by the `Lexer` to specify known errors.
+    """
+
+    def __init__(
+        self, message: str, cls: t.Type[TemplateSyntaxError] = TemplateSyntaxError
+    ) -> None:
+        self.message = message
+        self.error_class = cls
+
+    def __call__(self, lineno: int, filename: str) -> "te.NoReturn":
+        raise self.error_class(self.message, lineno, filename)
+
+
+class Token(t.NamedTuple):
+    lineno: int
+    type: str
+    value: str
+
+    def __str__(self) -> str:
+        return describe_token(self)
+
+    def test(self, expr: str) -> bool:
+        """Test a token against a token expression.  This can either be a
+        token type or ``'token_type:token_value'``.  This can only test
+        against string values and types.
+        """
+        # here we do a regular string equality check as test_any is usually
+        # passed an iterable of not interned strings.
+        if self.type == expr:
+            return True
+
+        if ":" in expr:
+            return expr.split(":", 1) == [self.type, self.value]
+
+        return False
+
+    def test_any(self, *iterable: str) -> bool:
+        """Test against multiple token expressions."""
+        return any(self.test(expr) for expr in iterable)
+
+
+class TokenStreamIterator:
+    """The iterator for tokenstreams.  Iterate over the stream
+    until the eof token is reached.
+    """
+
+    def __init__(self, stream: "TokenStream") -> None:
+        self.stream = stream
+
+    def __iter__(self) -> "TokenStreamIterator":
+        return self
+
+    def __next__(self) -> Token:
+        token = self.stream.current
+
+        if token.type is TOKEN_EOF:
+            self.stream.close()
+            raise StopIteration
+
+        next(self.stream)
+        return token
+
+
+class TokenStream:
+    """A token stream is an iterable that yields :class:`Token`\\s.  The
+    parser however does not iterate over it but calls :meth:`next` to go
+    one token ahead.  The current active token is stored as :attr:`current`.
+    """
+
+    def __init__(
+        self,
+        generator: t.Iterable[Token],
+        name: t.Optional[str],
+        filename: t.Optional[str],
+    ):
+        self._iter = iter(generator)
+        self._pushed: "te.Deque[Token]" = deque()
+        self.name = name
+        self.filename = filename
+        self.closed = False
+        self.current = Token(1, TOKEN_INITIAL, "")
+        next(self)
+
+    def __iter__(self) -> TokenStreamIterator:
+        return TokenStreamIterator(self)
+
+    def __bool__(self) -> bool:
+        return bool(self._pushed) or self.current.type is not TOKEN_EOF
+
+    @property
+    def eos(self) -> bool:
+        """Are we at the end of the stream?"""
+        return not self
+
+    def push(self, token: Token) -> None:
+        """Push a token back to the stream."""
+        self._pushed.append(token)
+
+    def look(self) -> Token:
+        """Look at the next token."""
+        old_token = next(self)
+        result = self.current
+        self.push(result)
+        self.current = old_token
+        return result
+
+    def skip(self, n: int = 1) -> None:
+        """Got n tokens ahead."""
+        for _ in range(n):
+            next(self)
+
+    def next_if(self, expr: str) -> t.Optional[Token]:
+        """Perform the token test and return the token if it matched.
+        Otherwise the return value is `None`.
+        """
+        if self.current.test(expr):
+            return next(self)
+
+        return None
+
+    def skip_if(self, expr: str) -> bool:
+        """Like :meth:`next_if` but only returns `True` or `False`."""
+        return self.next_if(expr) is not None
+
+    def __next__(self) -> Token:
+        """Go one token ahead and return the old one.
+
+        Use the built-in :func:`next` instead of calling this directly.
+        """
+        rv = self.current
+
+        if self._pushed:
+            self.current = self._pushed.popleft()
+        elif self.current.type is not TOKEN_EOF:
+            try:
+                self.current = next(self._iter)
+            except StopIteration:
+                self.close()
+
+        return rv
+
+    def close(self) -> None:
+        """Close the stream."""
+        self.current = Token(self.current.lineno, TOKEN_EOF, "")
+        self._iter = iter(())
+        self.closed = True
+
+    def expect(self, expr: str) -> Token:
+        """Expect a given token type and return it.  This accepts the same
+        argument as :meth:`jinja2.lexer.Token.test`.
+        """
+        if not self.current.test(expr):
+            expr = describe_token_expr(expr)
+
+            if self.current.type is TOKEN_EOF:
+                raise TemplateSyntaxError(
+                    f"unexpected end of template, expected {expr!r}.",
+                    self.current.lineno,
+                    self.name,
+                    self.filename,
+                )
+
+            raise TemplateSyntaxError(
+                f"expected token {expr!r}, got {describe_token(self.current)!r}",
+                self.current.lineno,
+                self.name,
+                self.filename,
+            )
+
+        return next(self)
+
+
+def get_lexer(environment: "Environment") -> "Lexer":
+    """Return a lexer which is probably cached."""
+    key = (
+        environment.block_start_string,
+        environment.block_end_string,
+        environment.variable_start_string,
+        environment.variable_end_string,
+        environment.comment_start_string,
+        environment.comment_end_string,
+        environment.line_statement_prefix,
+        environment.line_comment_prefix,
+        environment.trim_blocks,
+        environment.lstrip_blocks,
+        environment.newline_sequence,
+        environment.keep_trailing_newline,
+    )
+    lexer = _lexer_cache.get(key)
+
+    if lexer is None:
+        _lexer_cache[key] = lexer = Lexer(environment)
+
+    return lexer
+
+
+class OptionalLStrip(tuple):
+    """A special tuple for marking a point in the state that can have
+    lstrip applied.
+    """
+
+    __slots__ = ()
+
+    # Even though it looks like a no-op, creating instances fails
+    # without this.
+    def __new__(cls, *members, **kwargs):  # type: ignore
+        return super().__new__(cls, members)
+
+
+class _Rule(t.NamedTuple):
+    pattern: t.Pattern[str]
+    tokens: t.Union[str, t.Tuple[str, ...], t.Tuple[Failure]]
+    command: t.Optional[str]
+
+
+class Lexer:
+    """Class that implements a lexer for a given environment. Automatically
+    created by the environment class, usually you don't have to do that.
+
+    Note that the lexer is not automatically bound to an environment.
+    Multiple environments can share the same lexer.
+    """
+
+    def __init__(self, environment: "Environment") -> None:
+        # shortcuts
+        e = re.escape
+
+        def c(x: str) -> t.Pattern[str]:
+            return re.compile(x, re.M | re.S)
+
+        # lexing rules for tags
+        tag_rules: t.List[_Rule] = [
+            _Rule(whitespace_re, TOKEN_WHITESPACE, None),
+            _Rule(float_re, TOKEN_FLOAT, None),
+            _Rule(integer_re, TOKEN_INTEGER, None),
+            _Rule(name_re, TOKEN_NAME, None),
+            _Rule(string_re, TOKEN_STRING, None),
+            _Rule(operator_re, TOKEN_OPERATOR, None),
+        ]
+
+        # assemble the root lexing rule. because "|" is ungreedy
+        # we have to sort by length so that the lexer continues working
+        # as expected when we have parsing rules like <% for block and
+        # <%= for variables. (if someone wants asp like syntax)
+        # variables are just part of the rules if variable processing
+        # is required.
+        root_tag_rules = compile_rules(environment)
+
+        block_start_re = e(environment.block_start_string)
+        block_end_re = e(environment.block_end_string)
+        comment_end_re = e(environment.comment_end_string)
+        variable_end_re = e(environment.variable_end_string)
+
+        # block suffix if trimming is enabled
+        block_suffix_re = "\\n?" if environment.trim_blocks else ""
+
+        # If lstrip is enabled, it should not be applied if there is any
+        # non-whitespace between the newline and block.
+        self.lstrip_unless_re = c(r"[^ \t]") if environment.lstrip_blocks else None
+
+        self.newline_sequence = environment.newline_sequence
+        self.keep_trailing_newline = environment.keep_trailing_newline
+
+        root_raw_re = (
+            fr"(?P<raw_begin>{block_start_re}(\-|\+|)\s*raw\s*"
+            fr"(?:\-{block_end_re}\s*|{block_end_re}))"
+        )
+        root_parts_re = "|".join(
+            [root_raw_re] + [fr"(?P<{n}>{r}(\-|\+|))" for n, r in root_tag_rules]
+        )
+
+        # global lexing rules
+        self.rules: t.Dict[str, t.List[_Rule]] = {
+            "root": [
+                # directives
+                _Rule(
+                    c(fr"(.*?)(?:{root_parts_re})"),
+                    OptionalLStrip(TOKEN_DATA, "#bygroup"),  # type: ignore
+                    "#bygroup",
+                ),
+                # data
+                _Rule(c(".+"), TOKEN_DATA, None),
+            ],
+            # comments
+            TOKEN_COMMENT_BEGIN: [
+                _Rule(
+                    c(
+                        fr"(.*?)((?:\+{comment_end_re}|\-{comment_end_re}\s*"
+                        fr"|{comment_end_re}{block_suffix_re}))"
+                    ),
+                    (TOKEN_COMMENT, TOKEN_COMMENT_END),
+                    "#pop",
+                ),
+                _Rule(c(r"(.)"), (Failure("Missing end of comment tag"),), None),
+            ],
+            # blocks
+            TOKEN_BLOCK_BEGIN: [
+                _Rule(
+                    c(
+                        fr"(?:\+{block_end_re}|\-{block_end_re}\s*"
+                        fr"|{block_end_re}{block_suffix_re})"
+                    ),
+                    TOKEN_BLOCK_END,
+                    "#pop",
+                ),
+            ]
+            + tag_rules,
+            # variables
+            TOKEN_VARIABLE_BEGIN: [
+                _Rule(
+                    c(fr"\-{variable_end_re}\s*|{variable_end_re}"),
+                    TOKEN_VARIABLE_END,
+                    "#pop",
+                )
+            ]
+            + tag_rules,
+            # raw block
+            TOKEN_RAW_BEGIN: [
+                _Rule(
+                    c(
+                        fr"(.*?)((?:{block_start_re}(\-|\+|))\s*endraw\s*"
+                        fr"(?:\+{block_end_re}|\-{block_end_re}\s*"
+                        fr"|{block_end_re}{block_suffix_re}))"
+                    ),
+                    OptionalLStrip(TOKEN_DATA, TOKEN_RAW_END),  # type: ignore
+                    "#pop",
+                ),
+                _Rule(c(r"(.)"), (Failure("Missing end of raw directive"),), None),
+            ],
+            # line statements
+            TOKEN_LINESTATEMENT_BEGIN: [
+                _Rule(c(r"\s*(\n|$)"), TOKEN_LINESTATEMENT_END, "#pop")
+            ]
+            + tag_rules,
+            # line comments
+            TOKEN_LINECOMMENT_BEGIN: [
+                _Rule(
+                    c(r"(.*?)()(?=\n|$)"),
+                    (TOKEN_LINECOMMENT, TOKEN_LINECOMMENT_END),
+                    "#pop",
+                )
+            ],
+        }
+
+    def _normalize_newlines(self, value: str) -> str:
+        """Replace all newlines with the configured sequence in strings
+        and template data.
+        """
+        return newline_re.sub(self.newline_sequence, value)
+
+    def tokenize(
+        self,
+        source: str,
+        name: t.Optional[str] = None,
+        filename: t.Optional[str] = None,
+        state: t.Optional[str] = None,
+    ) -> TokenStream:
+        """Calls tokeniter + tokenize and wraps it in a token stream."""
+        stream = self.tokeniter(source, name, filename, state)
+        return TokenStream(self.wrap(stream, name, filename), name, filename)
+
+    def wrap(
+        self,
+        stream: t.Iterable[t.Tuple[int, str, str]],
+        name: t.Optional[str] = None,
+        filename: t.Optional[str] = None,
+    ) -> t.Iterator[Token]:
+        """This is called with the stream as returned by `tokenize` and wraps
+        every token in a :class:`Token` and converts the value.
+        """
+        for lineno, token, value_str in stream:
+            if token in ignored_tokens:
+                continue
+
+            value: t.Any = value_str
+
+            if token == TOKEN_LINESTATEMENT_BEGIN:
+                token = TOKEN_BLOCK_BEGIN
+            elif token == TOKEN_LINESTATEMENT_END:
+                token = TOKEN_BLOCK_END
+            # we are not interested in those tokens in the parser
+            elif token in (TOKEN_RAW_BEGIN, TOKEN_RAW_END):
+                continue
+            elif token == TOKEN_DATA:
+                value = self._normalize_newlines(value_str)
+            elif token == "keyword":
+                token = value_str
+            elif token == TOKEN_NAME:
+                value = value_str
+
+                if not value.isidentifier():
+                    raise TemplateSyntaxError(
+                        "Invalid character in identifier", lineno, name, filename
+                    )
+            elif token == TOKEN_STRING:
+                # try to unescape string
+                try:
+                    value = (
+                        self._normalize_newlines(value_str[1:-1])
+                        .encode("ascii", "backslashreplace")
+                        .decode("unicode-escape")
+                    )
+                except Exception as e:
+                    msg = str(e).split(":")[-1].strip()
+                    raise TemplateSyntaxError(msg, lineno, name, filename) from e
+            elif token == TOKEN_INTEGER:
+                value = int(value_str.replace("_", ""), 0)
+            elif token == TOKEN_FLOAT:
+                # remove all "_" first to support more Python versions
+                value = literal_eval(value_str.replace("_", ""))
+            elif token == TOKEN_OPERATOR:
+                token = operators[value_str]
+
+            yield Token(lineno, token, value)
+
+    def tokeniter(
+        self,
+        source: str,
+        name: t.Optional[str],
+        filename: t.Optional[str] = None,
+        state: t.Optional[str] = None,
+    ) -> t.Iterator[t.Tuple[int, str, str]]:
+        """This method tokenizes the text and returns the tokens in a
+        generator. Use this method if you just want to tokenize a template.
+
+        .. versionchanged:: 3.0
+            Only ``\\n``, ``\\r\\n`` and ``\\r`` are treated as line
+            breaks.
+        """
+        lines = newline_re.split(source)[::2]
+
+        if not self.keep_trailing_newline and lines[-1] == "":
+            del lines[-1]
+
+        source = "\n".join(lines)
+        pos = 0
+        lineno = 1
+        stack = ["root"]
+
+        if state is not None and state != "root":
+            assert state in ("variable", "block"), "invalid state"
+            stack.append(state + "_begin")
+
+        statetokens = self.rules[stack[-1]]
+        source_length = len(source)
+        balancing_stack: t.List[str] = []
+        lstrip_unless_re = self.lstrip_unless_re
+        newlines_stripped = 0
+        line_starting = True
+
+        while True:
+            # tokenizer loop
+            for regex, tokens, new_state in statetokens:
+                m = regex.match(source, pos)
+
+                # if no match we try again with the next rule
+                if m is None:
+                    continue
+
+                # we only match blocks and variables if braces / parentheses
+                # are balanced. continue parsing with the lower rule which
+                # is the operator rule. do this only if the end tags look
+                # like operators
+                if balancing_stack and tokens in (
+                    TOKEN_VARIABLE_END,
+                    TOKEN_BLOCK_END,
+                    TOKEN_LINESTATEMENT_END,
+                ):
+                    continue
+
+                # tuples support more options
+                if isinstance(tokens, tuple):
+                    groups = m.groups()
+
+                    if isinstance(tokens, OptionalLStrip):
+                        # Rule supports lstrip. Match will look like
+                        # text, block type, whitespace control, type, control, ...
+                        text = groups[0]
+                        # Skipping the text and first type, every other group is the
+                        # whitespace control for each type. One of the groups will be
+                        # -, +, or empty string instead of None.
+                        strip_sign = next(g for g in groups[2::2] if g is not None)
+
+                        if strip_sign == "-":
+                            # Strip all whitespace between the text and the tag.
+                            stripped = text.rstrip()
+                            newlines_stripped = text[len(stripped) :].count("\n")
+                            groups = [stripped, *groups[1:]]
+                        elif (
+                            # Not marked for preserving whitespace.
+                            strip_sign != "+"
+                            # lstrip is enabled.
+                            and lstrip_unless_re is not None
+                            # Not a variable expression.
+                            and not m.groupdict().get(TOKEN_VARIABLE_BEGIN)
+                        ):
+                            # The start of text between the last newline and the tag.
+                            l_pos = text.rfind("\n") + 1
+
+                            if l_pos > 0 or line_starting:
+                                # If there's only whitespace between the newline and the
+                                # tag, strip it.
+                                if not lstrip_unless_re.search(text, l_pos):
+                                    groups = [text[:l_pos], *groups[1:]]
+
+                    for idx, token in enumerate(tokens):
+                        # failure group
+                        if token.__class__ is Failure:
+                            raise token(lineno, filename)
+                        # bygroup is a bit more complex, in that case we
+                        # yield for the current token the first named
+                        # group that matched
+                        elif token == "#bygroup":
+                            for key, value in m.groupdict().items():
+                                if value is not None:
+                                    yield lineno, key, value
+                                    lineno += value.count("\n")
+                                    break
+                            else:
+                                raise RuntimeError(
+                                    f"{regex!r} wanted to resolve the token dynamically"
+                                    " but no group matched"
+                                )
+                        # normal group
+                        else:
+                            data = groups[idx]
+
+                            if data or token not in ignore_if_empty:
+                                yield lineno, token, data
+
+                            lineno += data.count("\n") + newlines_stripped
+                            newlines_stripped = 0
+
+                # strings as token just are yielded as it.
+                else:
+                    data = m.group()
+
+                    # update brace/parentheses balance
+                    if tokens == TOKEN_OPERATOR:
+                        if data == "{":
+                            balancing_stack.append("}")
+                        elif data == "(":
+                            balancing_stack.append(")")
+                        elif data == "[":
+                            balancing_stack.append("]")
+                        elif data in ("}", ")", "]"):
+                            if not balancing_stack:
+                                raise TemplateSyntaxError(
+                                    f"unexpected '{data}'", lineno, name, filename
+                                )
+
+                            expected_op = balancing_stack.pop()
+
+                            if expected_op != data:
+                                raise TemplateSyntaxError(
+                                    f"unexpected '{data}', expected '{expected_op}'",
+                                    lineno,
+                                    name,
+                                    filename,
+                                )
+
+                    # yield items
+                    if data or tokens not in ignore_if_empty:
+                        yield lineno, tokens, data
+
+                    lineno += data.count("\n")
+
+                line_starting = m.group()[-1:] == "\n"
+                # fetch new position into new variable so that we can check
+                # if there is a internal parsing error which would result
+                # in an infinite loop
+                pos2 = m.end()
+
+                # handle state changes
+                if new_state is not None:
+                    # remove the uppermost state
+                    if new_state == "#pop":
+                        stack.pop()
+                    # resolve the new state by group checking
+                    elif new_state == "#bygroup":
+                        for key, value in m.groupdict().items():
+                            if value is not None:
+                                stack.append(key)
+                                break
+                        else:
+                            raise RuntimeError(
+                                f"{regex!r} wanted to resolve the new state dynamically"
+                                f" but no group matched"
+                            )
+                    # direct state name given
+                    else:
+                        stack.append(new_state)
+
+                    statetokens = self.rules[stack[-1]]
+                # we are still at the same position and no stack change.
+                # this means a loop without break condition, avoid that and
+                # raise error
+                elif pos2 == pos:
+                    raise RuntimeError(
+                        f"{regex!r} yielded empty string without stack change"
+                    )
+
+                # publish new function and start again
+                pos = pos2
+                break
+            # if loop terminated without break we haven't found a single match
+            # either we are at the end of the file or we have a problem
+            else:
+                # end of text
+                if pos >= source_length:
+                    return
+
+                # something went wrong
+                raise TemplateSyntaxError(
+                    f"unexpected char {source[pos]!r} at {pos}", lineno, name, filename
+                )

lib/spack/external/_vendoring/jinja2/loaders.py

@@ -0,0 +1,652 @@
+"""API and implementations for loading templates from different data
+sources.
+"""
+import importlib.util
+import os
+import sys
+import typing as t
+import weakref
+import zipimport
+from collections import abc
+from hashlib import sha1
+from importlib import import_module
+from types import ModuleType
+
+from .exceptions import TemplateNotFound
+from .utils import internalcode
+from .utils import open_if_exists
+
+if t.TYPE_CHECKING:
+    from .environment import Environment
+    from .environment import Template
+
+
+def split_template_path(template: str) -> t.List[str]:
+    """Split a path into segments and perform a sanity check.  If it detects
+    '..' in the path it will raise a `TemplateNotFound` error.
+    """
+    pieces = []
+    for piece in template.split("/"):
+        if (
+            os.path.sep in piece
+            or (os.path.altsep and os.path.altsep in piece)
+            or piece == os.path.pardir
+        ):
+            raise TemplateNotFound(template)
+        elif piece and piece != ".":
+            pieces.append(piece)
+    return pieces
+
+
+class BaseLoader:
+    """Baseclass for all loaders.  Subclass this and override `get_source` to
+    implement a custom loading mechanism.  The environment provides a
+    `get_template` method that calls the loader's `load` method to get the
+    :class:`Template` object.
+
+    A very basic example for a loader that looks up templates on the file
+    system could look like this::
+
+        from jinja2 import BaseLoader, TemplateNotFound
+        from os.path import join, exists, getmtime
+
+        class MyLoader(BaseLoader):
+
+            def __init__(self, path):
+                self.path = path
+
+            def get_source(self, environment, template):
+                path = join(self.path, template)
+                if not exists(path):
+                    raise TemplateNotFound(template)
+                mtime = getmtime(path)
+                with open(path) as f:
+                    source = f.read()
+                return source, path, lambda: mtime == getmtime(path)
+    """
+
+    #: if set to `False` it indicates that the loader cannot provide access
+    #: to the source of templates.
+    #:
+    #: .. versionadded:: 2.4
+    has_source_access = True
+
+    def get_source(
+        self, environment: "Environment", template: str
+    ) -> t.Tuple[str, t.Optional[str], t.Optional[t.Callable[[], bool]]]:
+        """Get the template source, filename and reload helper for a template.
+        It's passed the environment and template name and has to return a
+        tuple in the form ``(source, filename, uptodate)`` or raise a
+        `TemplateNotFound` error if it can't locate the template.
+
+        The source part of the returned tuple must be the source of the
+        template as a string. The filename should be the name of the
+        file on the filesystem if it was loaded from there, otherwise
+        ``None``. The filename is used by Python for the tracebacks
+        if no loader extension is used.
+
+        The last item in the tuple is the `uptodate` function.  If auto
+        reloading is enabled it's always called to check if the template
+        changed.  No arguments are passed so the function must store the
+        old state somewhere (for example in a closure).  If it returns `False`
+        the template will be reloaded.
+        """
+        if not self.has_source_access:
+            raise RuntimeError(
+                f"{type(self).__name__} cannot provide access to the source"
+            )
+        raise TemplateNotFound(template)
+
+    def list_templates(self) -> t.List[str]:
+        """Iterates over all templates.  If the loader does not support that
+        it should raise a :exc:`TypeError` which is the default behavior.
+        """
+        raise TypeError("this loader cannot iterate over all templates")
+
+    @internalcode
+    def load(
+        self,
+        environment: "Environment",
+        name: str,
+        globals: t.Optional[t.MutableMapping[str, t.Any]] = None,
+    ) -> "Template":
+        """Loads a template.  This method looks up the template in the cache
+        or loads one by calling :meth:`get_source`.  Subclasses should not
+        override this method as loaders working on collections of other
+        loaders (such as :class:`PrefixLoader` or :class:`ChoiceLoader`)
+        will not call this method but `get_source` directly.
+        """
+        code = None
+        if globals is None:
+            globals = {}
+
+        # first we try to get the source for this template together
+        # with the filename and the uptodate function.
+        source, filename, uptodate = self.get_source(environment, name)
+
+        # try to load the code from the bytecode cache if there is a
+        # bytecode cache configured.
+        bcc = environment.bytecode_cache
+        if bcc is not None:
+            bucket = bcc.get_bucket(environment, name, filename, source)
+            code = bucket.code
+
+        # if we don't have code so far (not cached, no longer up to
+        # date) etc. we compile the template
+        if code is None:
+            code = environment.compile(source, name, filename)
+
+        # if the bytecode cache is available and the bucket doesn't
+        # have a code so far, we give the bucket the new code and put
+        # it back to the bytecode cache.
+        if bcc is not None and bucket.code is None:
+            bucket.code = code
+            bcc.set_bucket(bucket)
+
+        return environment.template_class.from_code(
+            environment, code, globals, uptodate
+        )
+
+
+class FileSystemLoader(BaseLoader):
+    """Load templates from a directory in the file system.
+
+    The path can be relative or absolute. Relative paths are relative to
+    the current working directory.
+
+    .. code-block:: python
+
+        loader = FileSystemLoader("templates")
+
+    A list of paths can be given. The directories will be searched in
+    order, stopping at the first matching template.
+
+    .. code-block:: python
+
+        loader = FileSystemLoader(["/override/templates", "/default/templates"])
+
+    :param searchpath: A path, or list of paths, to the directory that
+        contains the templates.
+    :param encoding: Use this encoding to read the text from template
+        files.
+    :param followlinks: Follow symbolic links in the path.
+
+    .. versionchanged:: 2.8
+        Added the ``followlinks`` parameter.
+    """
+
+    def __init__(
+        self,
+        searchpath: t.Union[str, os.PathLike, t.Sequence[t.Union[str, os.PathLike]]],
+        encoding: str = "utf-8",
+        followlinks: bool = False,
+    ) -> None:
+        if not isinstance(searchpath, abc.Iterable) or isinstance(searchpath, str):
+            searchpath = [searchpath]
+
+        self.searchpath = [os.fspath(p) for p in searchpath]
+        self.encoding = encoding
+        self.followlinks = followlinks
+
+    def get_source(
+        self, environment: "Environment", template: str
+    ) -> t.Tuple[str, str, t.Callable[[], bool]]:
+        pieces = split_template_path(template)
+        for searchpath in self.searchpath:
+            filename = os.path.join(searchpath, *pieces)
+            f = open_if_exists(filename)
+            if f is None:
+                continue
+            try:
+                contents = f.read().decode(self.encoding)
+            finally:
+                f.close()
+
+            mtime = os.path.getmtime(filename)
+
+            def uptodate() -> bool:
+                try:
+                    return os.path.getmtime(filename) == mtime
+                except OSError:
+                    return False
+
+            return contents, filename, uptodate
+        raise TemplateNotFound(template)
+
+    def list_templates(self) -> t.List[str]:
+        found = set()
+        for searchpath in self.searchpath:
+            walk_dir = os.walk(searchpath, followlinks=self.followlinks)
+            for dirpath, _, filenames in walk_dir:
+                for filename in filenames:
+                    template = (
+                        os.path.join(dirpath, filename)[len(searchpath) :]
+                        .strip(os.path.sep)
+                        .replace(os.path.sep, "/")
+                    )
+                    if template[:2] == "./":
+                        template = template[2:]
+                    if template not in found:
+                        found.add(template)
+        return sorted(found)
+
+
+class PackageLoader(BaseLoader):
+    """Load templates from a directory in a Python package.
+
+    :param package_name: Import name of the package that contains the
+        template directory.
+    :param package_path: Directory within the imported package that
+        contains the templates.
+    :param encoding: Encoding of template files.
+
+    The following example looks up templates in the ``pages`` directory
+    within the ``project.ui`` package.
+
+    .. code-block:: python
+
+        loader = PackageLoader("project.ui", "pages")
+
+    Only packages installed as directories (standard pip behavior) or
+    zip/egg files (less common) are supported. The Python API for
+    introspecting data in packages is too limited to support other
+    installation methods the way this loader requires.
+
+    There is limited support for :pep:`420` namespace packages. The
+    template directory is assumed to only be in one namespace
+    contributor. Zip files contributing to a namespace are not
+    supported.
+
+    .. versionchanged:: 3.0
+        No longer uses ``setuptools`` as a dependency.
+
+    .. versionchanged:: 3.0
+        Limited PEP 420 namespace package support.
+    """
+
+    def __init__(
+        self,
+        package_name: str,
+        package_path: "str" = "templates",
+        encoding: str = "utf-8",
+    ) -> None:
+        package_path = os.path.normpath(package_path).rstrip(os.path.sep)
+
+        # normpath preserves ".", which isn't valid in zip paths.
+        if package_path == os.path.curdir:
+            package_path = ""
+        elif package_path[:2] == os.path.curdir + os.path.sep:
+            package_path = package_path[2:]
+
+        self.package_path = package_path
+        self.package_name = package_name
+        self.encoding = encoding
+
+        # Make sure the package exists. This also makes namespace
+        # packages work, otherwise get_loader returns None.
+        import_module(package_name)
+        spec = importlib.util.find_spec(package_name)
+        assert spec is not None, "An import spec was not found for the package."
+        loader = spec.loader
+        assert loader is not None, "A loader was not found for the package."
+        self._loader = loader
+        self._archive = None
+        template_root = None
+
+        if isinstance(loader, zipimport.zipimporter):
+            self._archive = loader.archive
+            pkgdir = next(iter(spec.submodule_search_locations))  # type: ignore
+            template_root = os.path.join(pkgdir, package_path)
+        else:
+            roots: t.List[str] = []
+
+            # One element for regular packages, multiple for namespace
+            # packages, or None for single module file.
+            if spec.submodule_search_locations:
+                roots.extend(spec.submodule_search_locations)
+            # A single module file, use the parent directory instead.
+            elif spec.origin is not None:
+                roots.append(os.path.dirname(spec.origin))
+
+            for root in roots:
+                root = os.path.join(root, package_path)
+
+                if os.path.isdir(root):
+                    template_root = root
+                    break
+
+        if template_root is None:
+            raise ValueError(
+                f"The {package_name!r} package was not installed in a"
+                " way that PackageLoader understands."
+            )
+
+        self._template_root = template_root
+
+    def get_source(
+        self, environment: "Environment", template: str
+    ) -> t.Tuple[str, str, t.Optional[t.Callable[[], bool]]]:
+        p = os.path.join(self._template_root, *split_template_path(template))
+        up_to_date: t.Optional[t.Callable[[], bool]]
+
+        if self._archive is None:
+            # Package is a directory.
+            if not os.path.isfile(p):
+                raise TemplateNotFound(template)
+
+            with open(p, "rb") as f:
+                source = f.read()
+
+            mtime = os.path.getmtime(p)
+
+            def up_to_date() -> bool:
+                return os.path.isfile(p) and os.path.getmtime(p) == mtime
+
+        else:
+            # Package is a zip file.
+            try:
+                source = self._loader.get_data(p)  # type: ignore
+            except OSError as e:
+                raise TemplateNotFound(template) from e
+
+            # Could use the zip's mtime for all template mtimes, but
+            # would need to safely reload the module if it's out of
+            # date, so just report it as always current.
+            up_to_date = None
+
+        return source.decode(self.encoding), p, up_to_date
+
+    def list_templates(self) -> t.List[str]:
+        results: t.List[str] = []
+
+        if self._archive is None:
+            # Package is a directory.
+            offset = len(self._template_root)
+
+            for dirpath, _, filenames in os.walk(self._template_root):
+                dirpath = dirpath[offset:].lstrip(os.path.sep)
+                results.extend(
+                    os.path.join(dirpath, name).replace(os.path.sep, "/")
+                    for name in filenames
+                )
+        else:
+            if not hasattr(self._loader, "_files"):
+                raise TypeError(
+                    "This zip import does not have the required"
+                    " metadata to list templates."
+                )
+
+            # Package is a zip file.
+            prefix = (
+                self._template_root[len(self._archive) :].lstrip(os.path.sep)
+                + os.path.sep
+            )
+            offset = len(prefix)
+
+            for name in self._loader._files.keys():  # type: ignore
+                # Find names under the templates directory that aren't directories.
+                if name.startswith(prefix) and name[-1] != os.path.sep:
+                    results.append(name[offset:].replace(os.path.sep, "/"))
+
+        results.sort()
+        return results
+
+
+class DictLoader(BaseLoader):
+    """Loads a template from a Python dict mapping template names to
+    template source.  This loader is useful for unittesting:
+
+    >>> loader = DictLoader({'index.html': 'source here'})
+
+    Because auto reloading is rarely useful this is disabled per default.
+    """
+
+    def __init__(self, mapping: t.Mapping[str, str]) -> None:
+        self.mapping = mapping
+
+    def get_source(
+        self, environment: "Environment", template: str
+    ) -> t.Tuple[str, None, t.Callable[[], bool]]:
+        if template in self.mapping:
+            source = self.mapping[template]
+            return source, None, lambda: source == self.mapping.get(template)
+        raise TemplateNotFound(template)
+
+    def list_templates(self) -> t.List[str]:
+        return sorted(self.mapping)
+
+
+class FunctionLoader(BaseLoader):
+    """A loader that is passed a function which does the loading.  The
+    function receives the name of the template and has to return either
+    a string with the template source, a tuple in the form ``(source,
+    filename, uptodatefunc)`` or `None` if the template does not exist.
+
+    >>> def load_template(name):
+    ...     if name == 'index.html':
+    ...         return '...'
+    ...
+    >>> loader = FunctionLoader(load_template)
+
+    The `uptodatefunc` is a function that is called if autoreload is enabled
+    and has to return `True` if the template is still up to date.  For more
+    details have a look at :meth:`BaseLoader.get_source` which has the same
+    return value.
+    """
+
+    def __init__(
+        self,
+        load_func: t.Callable[
+            [str],
+            t.Optional[
+                t.Union[
+                    str, t.Tuple[str, t.Optional[str], t.Optional[t.Callable[[], bool]]]
+                ]
+            ],
+        ],
+    ) -> None:
+        self.load_func = load_func
+
+    def get_source(
+        self, environment: "Environment", template: str
+    ) -> t.Tuple[str, t.Optional[str], t.Optional[t.Callable[[], bool]]]:
+        rv = self.load_func(template)
+
+        if rv is None:
+            raise TemplateNotFound(template)
+
+        if isinstance(rv, str):
+            return rv, None, None
+
+        return rv
+
+
+class PrefixLoader(BaseLoader):
+    """A loader that is passed a dict of loaders where each loader is bound
+    to a prefix.  The prefix is delimited from the template by a slash per
+    default, which can be changed by setting the `delimiter` argument to
+    something else::
+
+        loader = PrefixLoader({
+            'app1':     PackageLoader('mypackage.app1'),
+            'app2':     PackageLoader('mypackage.app2')
+        })
+
+    By loading ``'app1/index.html'`` the file from the app1 package is loaded,
+    by loading ``'app2/index.html'`` the file from the second.
+    """
+
+    def __init__(
+        self, mapping: t.Mapping[str, BaseLoader], delimiter: str = "/"
+    ) -> None:
+        self.mapping = mapping
+        self.delimiter = delimiter
+
+    def get_loader(self, template: str) -> t.Tuple[BaseLoader, str]:
+        try:
+            prefix, name = template.split(self.delimiter, 1)
+            loader = self.mapping[prefix]
+        except (ValueError, KeyError) as e:
+            raise TemplateNotFound(template) from e
+        return loader, name
+
+    def get_source(
+        self, environment: "Environment", template: str
+    ) -> t.Tuple[str, t.Optional[str], t.Optional[t.Callable[[], bool]]]:
+        loader, name = self.get_loader(template)
+        try:
+            return loader.get_source(environment, name)
+        except TemplateNotFound as e:
+            # re-raise the exception with the correct filename here.
+            # (the one that includes the prefix)
+            raise TemplateNotFound(template) from e
+
+    @internalcode
+    def load(
+        self,
+        environment: "Environment",
+        name: str,
+        globals: t.Optional[t.MutableMapping[str, t.Any]] = None,
+    ) -> "Template":
+        loader, local_name = self.get_loader(name)
+        try:
+            return loader.load(environment, local_name, globals)
+        except TemplateNotFound as e:
+            # re-raise the exception with the correct filename here.
+            # (the one that includes the prefix)
+            raise TemplateNotFound(name) from e
+
+    def list_templates(self) -> t.List[str]:
+        result = []
+        for prefix, loader in self.mapping.items():
+            for template in loader.list_templates():
+                result.append(prefix + self.delimiter + template)
+        return result
+
+
+class ChoiceLoader(BaseLoader):
+    """This loader works like the `PrefixLoader` just that no prefix is
+    specified.  If a template could not be found by one loader the next one
+    is tried.
+
+    >>> loader = ChoiceLoader([
+    ...     FileSystemLoader('/path/to/user/templates'),
+    ...     FileSystemLoader('/path/to/system/templates')
+    ... ])
+
+    This is useful if you want to allow users to override builtin templates
+    from a different location.
+    """
+
+    def __init__(self, loaders: t.Sequence[BaseLoader]) -> None:
+        self.loaders = loaders
+
+    def get_source(
+        self, environment: "Environment", template: str
+    ) -> t.Tuple[str, t.Optional[str], t.Optional[t.Callable[[], bool]]]:
+        for loader in self.loaders:
+            try:
+                return loader.get_source(environment, template)
+            except TemplateNotFound:
+                pass
+        raise TemplateNotFound(template)
+
+    @internalcode
+    def load(
+        self,
+        environment: "Environment",
+        name: str,
+        globals: t.Optional[t.MutableMapping[str, t.Any]] = None,
+    ) -> "Template":
+        for loader in self.loaders:
+            try:
+                return loader.load(environment, name, globals)
+            except TemplateNotFound:
+                pass
+        raise TemplateNotFound(name)
+
+    def list_templates(self) -> t.List[str]:
+        found = set()
+        for loader in self.loaders:
+            found.update(loader.list_templates())
+        return sorted(found)
+
+
+class _TemplateModule(ModuleType):
+    """Like a normal module but with support for weak references"""
+
+
+class ModuleLoader(BaseLoader):
+    """This loader loads templates from precompiled templates.
+
+    Example usage:
+
+    >>> loader = ChoiceLoader([
+    ...     ModuleLoader('/path/to/compiled/templates'),
+    ...     FileSystemLoader('/path/to/templates')
+    ... ])
+
+    Templates can be precompiled with :meth:`Environment.compile_templates`.
+    """
+
+    has_source_access = False
+
+    def __init__(
+        self, path: t.Union[str, os.PathLike, t.Sequence[t.Union[str, os.PathLike]]]
+    ) -> None:
+        package_name = f"_jinja2_module_templates_{id(self):x}"
+
+        # create a fake module that looks for the templates in the
+        # path given.
+        mod = _TemplateModule(package_name)
+
+        if not isinstance(path, abc.Iterable) or isinstance(path, str):
+            path = [path]
+
+        mod.__path__ = [os.fspath(p) for p in path]  # type: ignore
+
+        sys.modules[package_name] = weakref.proxy(
+            mod, lambda x: sys.modules.pop(package_name, None)
+        )
+
+        # the only strong reference, the sys.modules entry is weak
+        # so that the garbage collector can remove it once the
+        # loader that created it goes out of business.
+        self.module = mod
+        self.package_name = package_name
+
+    @staticmethod
+    def get_template_key(name: str) -> str:
+        return "tmpl_" + sha1(name.encode("utf-8")).hexdigest()
+
+    @staticmethod
+    def get_module_filename(name: str) -> str:
+        return ModuleLoader.get_template_key(name) + ".py"
+
+    @internalcode
+    def load(
+        self,
+        environment: "Environment",
+        name: str,
+        globals: t.Optional[t.MutableMapping[str, t.Any]] = None,
+    ) -> "Template":
+        key = self.get_template_key(name)
+        module = f"{self.package_name}.{key}"
+        mod = getattr(self.module, module, None)
+
+        if mod is None:
+            try:
+                mod = __import__(module, None, None, ["root"])
+            except ImportError as e:
+                raise TemplateNotFound(name) from e
+
+            # remove the entry from sys.modules, we only want the attribute
+            # on the module object we have stored on the loader.
+            sys.modules.pop(module, None)
+
+        if globals is None:
+            globals = {}
+
+        return environment.template_class.from_module_dict(
+            environment, mod.__dict__, globals
+        )

lib/spack/external/_vendoring/jinja2/meta.py

@@ -0,0 +1,111 @@
+"""Functions that expose information about templates that might be
+interesting for introspection.
+"""
+import typing as t
+
+from . import nodes
+from .compiler import CodeGenerator
+from .compiler import Frame
+
+if t.TYPE_CHECKING:
+    from .environment import Environment
+
+
+class TrackingCodeGenerator(CodeGenerator):
+    """We abuse the code generator for introspection."""
+
+    def __init__(self, environment: "Environment") -> None:
+        super().__init__(environment, "<introspection>", "<introspection>")
+        self.undeclared_identifiers: t.Set[str] = set()
+
+    def write(self, x: str) -> None:
+        """Don't write."""
+
+    def enter_frame(self, frame: Frame) -> None:
+        """Remember all undeclared identifiers."""
+        super().enter_frame(frame)
+
+        for _, (action, param) in frame.symbols.loads.items():
+            if action == "resolve" and param not in self.environment.globals:
+                self.undeclared_identifiers.add(param)
+
+
+def find_undeclared_variables(ast: nodes.Template) -> t.Set[str]:
+    """Returns a set of all variables in the AST that will be looked up from
+    the context at runtime.  Because at compile time it's not known which
+    variables will be used depending on the path the execution takes at
+    runtime, all variables are returned.
+
+    >>> from jinja2 import Environment, meta
+    >>> env = Environment()
+    >>> ast = env.parse('{% set foo = 42 %}{{ bar + foo }}')
+    >>> meta.find_undeclared_variables(ast) == {'bar'}
+    True
+
+    .. admonition:: Implementation
+
+       Internally the code generator is used for finding undeclared variables.
+       This is good to know because the code generator might raise a
+       :exc:`TemplateAssertionError` during compilation and as a matter of
+       fact this function can currently raise that exception as well.
+    """
+    codegen = TrackingCodeGenerator(ast.environment)  # type: ignore
+    codegen.visit(ast)
+    return codegen.undeclared_identifiers
+
+
+_ref_types = (nodes.Extends, nodes.FromImport, nodes.Import, nodes.Include)
+_RefType = t.Union[nodes.Extends, nodes.FromImport, nodes.Import, nodes.Include]
+
+
+def find_referenced_templates(ast: nodes.Template) -> t.Iterator[t.Optional[str]]:
+    """Finds all the referenced templates from the AST.  This will return an
+    iterator over all the hardcoded template extensions, inclusions and
+    imports.  If dynamic inheritance or inclusion is used, `None` will be
+    yielded.
+
+    >>> from jinja2 import Environment, meta
+    >>> env = Environment()
+    >>> ast = env.parse('{% extends "layout.html" %}{% include helper %}')
+    >>> list(meta.find_referenced_templates(ast))
+    ['layout.html', None]
+
+    This function is useful for dependency tracking.  For example if you want
+    to rebuild parts of the website after a layout template has changed.
+    """
+    template_name: t.Any
+
+    for node in ast.find_all(_ref_types):
+        template: nodes.Expr = node.template  # type: ignore
+
+        if not isinstance(template, nodes.Const):
+            # a tuple with some non consts in there
+            if isinstance(template, (nodes.Tuple, nodes.List)):
+                for template_name in template.items:
+                    # something const, only yield the strings and ignore
+                    # non-string consts that really just make no sense
+                    if isinstance(template_name, nodes.Const):
+                        if isinstance(template_name.value, str):
+                            yield template_name.value
+                    # something dynamic in there
+                    else:
+                        yield None
+            # something dynamic we don't know about here
+            else:
+                yield None
+            continue
+        # constant is a basestring, direct template name
+        if isinstance(template.value, str):
+            yield template.value
+        # a tuple or list (latter *should* not happen) made of consts,
+        # yield the consts that are strings.  We could warn here for
+        # non string values
+        elif isinstance(node, nodes.Include) and isinstance(
+            template.value, (tuple, list)
+        ):
+            for template_name in template.value:
+                if isinstance(template_name, str):
+                    yield template_name
+        # something else we don't care about, we could warn here
+        else:
+            yield None

lib/spack/external/_vendoring/jinja2/nativetypes.py

@@ -0,0 +1,124 @@
+import typing as t
+from ast import literal_eval
+from ast import parse
+from itertools import chain
+from itertools import islice
+
+from . import nodes
+from .compiler import CodeGenerator
+from .compiler import Frame
+from .compiler import has_safe_repr
+from .environment import Environment
+from .environment import Template
+
+
+def native_concat(values: t.Iterable[t.Any]) -> t.Optional[t.Any]:
+    """Return a native Python type from the list of compiled nodes. If
+    the result is a single node, its value is returned. Otherwise, the
+    nodes are concatenated as strings. If the result can be parsed with
+    :func:`ast.literal_eval`, the parsed value is returned. Otherwise,
+    the string is returned.
+
+    :param values: Iterable of outputs to concatenate.
+    """
+    head = list(islice(values, 2))
+
+    if not head:
+        return None
+
+    if len(head) == 1:
+        raw = head[0]
+        if not isinstance(raw, str):
+            return raw
+    else:
+        raw = "".join([str(v) for v in chain(head, values)])
+
+    try:
+        return literal_eval(
+            # In Python 3.10+ ast.literal_eval removes leading spaces/tabs
+            # from the given string. For backwards compatibility we need to
+            # parse the string ourselves without removing leading spaces/tabs.
+            parse(raw, mode="eval")
+        )
+    except (ValueError, SyntaxError, MemoryError):
+        return raw
+
+
+class NativeCodeGenerator(CodeGenerator):
+    """A code generator which renders Python types by not adding
+    ``str()`` around output nodes.
+    """
+
+    @staticmethod
+    def _default_finalize(value: t.Any) -> t.Any:
+        return value
+
+    def _output_const_repr(self, group: t.Iterable[t.Any]) -> str:
+        return repr("".join([str(v) for v in group]))
+
+    def _output_child_to_const(
+        self, node: nodes.Expr, frame: Frame, finalize: CodeGenerator._FinalizeInfo
+    ) -> t.Any:
+        const = node.as_const(frame.eval_ctx)
+
+        if not has_safe_repr(const):
+            raise nodes.Impossible()
+
+        if isinstance(node, nodes.TemplateData):
+            return const
+
+        return finalize.const(const)  # type: ignore
+
+    def _output_child_pre(
+        self, node: nodes.Expr, frame: Frame, finalize: CodeGenerator._FinalizeInfo
+    ) -> None:
+        if finalize.src is not None:
+            self.write(finalize.src)
+
+    def _output_child_post(
+        self, node: nodes.Expr, frame: Frame, finalize: CodeGenerator._FinalizeInfo
+    ) -> None:
+        if finalize.src is not None:
+            self.write(")")
+
+
+class NativeEnvironment(Environment):
+    """An environment that renders templates to native Python types."""
+
+    code_generator_class = NativeCodeGenerator
+
+
+class NativeTemplate(Template):
+    environment_class = NativeEnvironment
+
+    def render(self, *args: t.Any, **kwargs: t.Any) -> t.Any:
+        """Render the template to produce a native Python type. If the
+        result is a single node, its value is returned. Otherwise, the
+        nodes are concatenated as strings. If the result can be parsed
+        with :func:`ast.literal_eval`, the parsed value is returned.
+        Otherwise, the string is returned.
+        """
+        ctx = self.new_context(dict(*args, **kwargs))
+
+        try:
+            return native_concat(self.root_render_func(ctx))  # type: ignore
+        except Exception:
+            return self.environment.handle_exception()
+
+    async def render_async(self, *args: t.Any, **kwargs: t.Any) -> t.Any:
+        if not self.environment.is_async:
+            raise RuntimeError(
+                "The environment was not created with async mode enabled."
+            )
+
+        ctx = self.new_context(dict(*args, **kwargs))
+
+        try:
+            return native_concat(
+                [n async for n in self.root_render_func(ctx)]  # type: ignore
+            )
+        except Exception:
+            return self.environment.handle_exception()
+
+
+NativeEnvironment.template_class = NativeTemplate

lib/spack/external/_vendoring/jinja2/optimizer.py

@@ -0,0 +1,47 @@
+"""The optimizer tries to constant fold expressions and modify the AST
+in place so that it should be faster to evaluate.
+
+Because the AST does not contain all the scoping information and the
+compiler has to find that out, we cannot do all the optimizations we
+want. For example, loop unrolling doesn't work because unrolled loops
+would have a different scope. The solution would be a second syntax tree
+that stored the scoping rules.
+"""
+import typing as t
+
+from . import nodes
+from .visitor import NodeTransformer
+
+if t.TYPE_CHECKING:
+    from .environment import Environment
+
+
+def optimize(node: nodes.Node, environment: "Environment") -> nodes.Node:
+    """The context hint can be used to perform an static optimization
+    based on the context given."""
+    optimizer = Optimizer(environment)
+    return t.cast(nodes.Node, optimizer.visit(node))
+
+
+class Optimizer(NodeTransformer):
+    def __init__(self, environment: "t.Optional[Environment]") -> None:
+        self.environment = environment
+
+    def generic_visit(
+        self, node: nodes.Node, *args: t.Any, **kwargs: t.Any
+    ) -> nodes.Node:
+        node = super().generic_visit(node, *args, **kwargs)
+
+        # Do constant folding. Some other nodes besides Expr have
+        # as_const, but folding them causes errors later on.
+        if isinstance(node, nodes.Expr):
+            try:
+                return nodes.Const.from_untrusted(
+                    node.as_const(args[0] if args else None),
+                    lineno=node.lineno,
+                    environment=self.environment,
+                )
+            except nodes.Impossible:
+                pass
+
+        return node

lib/spack/external/_vendoring/jinja2/sandbox.py

@@ -0,0 +1,428 @@
+"""A sandbox layer that ensures unsafe operations cannot be performed.
+Useful when the template itself comes from an untrusted source.
+"""
+import operator
+import types
+import typing as t
+from _string import formatter_field_name_split  # type: ignore
+from collections import abc
+from collections import deque
+from string import Formatter
+
+from markupsafe import EscapeFormatter
+from markupsafe import Markup
+
+from .environment import Environment
+from .exceptions import SecurityError
+from .runtime import Context
+from .runtime import Undefined
+
+F = t.TypeVar("F", bound=t.Callable[..., t.Any])
+
+#: maximum number of items a range may produce
+MAX_RANGE = 100000
+
+#: Unsafe function attributes.
+UNSAFE_FUNCTION_ATTRIBUTES: t.Set[str] = set()
+
+#: Unsafe method attributes. Function attributes are unsafe for methods too.
+UNSAFE_METHOD_ATTRIBUTES: t.Set[str] = set()
+
+#: unsafe generator attributes.
+UNSAFE_GENERATOR_ATTRIBUTES = {"gi_frame", "gi_code"}
+
+#: unsafe attributes on coroutines
+UNSAFE_COROUTINE_ATTRIBUTES = {"cr_frame", "cr_code"}
+
+#: unsafe attributes on async generators
+UNSAFE_ASYNC_GENERATOR_ATTRIBUTES = {"ag_code", "ag_frame"}
+
+_mutable_spec: t.Tuple[t.Tuple[t.Type, t.FrozenSet[str]], ...] = (
+    (
+        abc.MutableSet,
+        frozenset(
+            [
+                "add",
+                "clear",
+                "difference_update",
+                "discard",
+                "pop",
+                "remove",
+                "symmetric_difference_update",
+                "update",
+            ]
+        ),
+    ),
+    (
+        abc.MutableMapping,
+        frozenset(["clear", "pop", "popitem", "setdefault", "update"]),
+    ),
+    (
+        abc.MutableSequence,
+        frozenset(["append", "reverse", "insert", "sort", "extend", "remove"]),
+    ),
+    (
+        deque,
+        frozenset(
+            [
+                "append",
+                "appendleft",
+                "clear",
+                "extend",
+                "extendleft",
+                "pop",
+                "popleft",
+                "remove",
+                "rotate",
+            ]
+        ),
+    ),
+)
+
+
+def inspect_format_method(callable: t.Callable) -> t.Optional[str]:
+    if not isinstance(
+        callable, (types.MethodType, types.BuiltinMethodType)
+    ) or callable.__name__ not in ("format", "format_map"):
+        return None
+
+    obj = callable.__self__
+
+    if isinstance(obj, str):
+        return obj
+
+    return None
+
+
+def safe_range(*args: int) -> range:
+    """A range that can't generate ranges with a length of more than
+    MAX_RANGE items.
+    """
+    rng = range(*args)
+
+    if len(rng) > MAX_RANGE:
+        raise OverflowError(
+            "Range too big. The sandbox blocks ranges larger than"
+            f" MAX_RANGE ({MAX_RANGE})."
+        )
+
+    return rng
+
+
+def unsafe(f: F) -> F:
+    """Marks a function or method as unsafe.
+
+    .. code-block: python
+
+        @unsafe
+        def delete(self):
+            pass
+    """
+    f.unsafe_callable = True  # type: ignore
+    return f
+
+
+def is_internal_attribute(obj: t.Any, attr: str) -> bool:
+    """Test if the attribute given is an internal python attribute.  For
+    example this function returns `True` for the `func_code` attribute of
+    python objects.  This is useful if the environment method
+    :meth:`~SandboxedEnvironment.is_safe_attribute` is overridden.
+
+    >>> from jinja2.sandbox import is_internal_attribute
+    >>> is_internal_attribute(str, "mro")
+    True
+    >>> is_internal_attribute(str, "upper")
+    False
+    """
+    if isinstance(obj, types.FunctionType):
+        if attr in UNSAFE_FUNCTION_ATTRIBUTES:
+            return True
+    elif isinstance(obj, types.MethodType):
+        if attr in UNSAFE_FUNCTION_ATTRIBUTES or attr in UNSAFE_METHOD_ATTRIBUTES:
+            return True
+    elif isinstance(obj, type):
+        if attr == "mro":
+            return True
+    elif isinstance(obj, (types.CodeType, types.TracebackType, types.FrameType)):
+        return True
+    elif isinstance(obj, types.GeneratorType):
+        if attr in UNSAFE_GENERATOR_ATTRIBUTES:
+            return True
+    elif hasattr(types, "CoroutineType") and isinstance(obj, types.CoroutineType):
+        if attr in UNSAFE_COROUTINE_ATTRIBUTES:
+            return True
+    elif hasattr(types, "AsyncGeneratorType") and isinstance(
+        obj, types.AsyncGeneratorType
+    ):
+        if attr in UNSAFE_ASYNC_GENERATOR_ATTRIBUTES:
+            return True
+    return attr.startswith("__")
+
+
+def modifies_known_mutable(obj: t.Any, attr: str) -> bool:
+    """This function checks if an attribute on a builtin mutable object
+    (list, dict, set or deque) or the corresponding ABCs would modify it
+    if called.
+
+    >>> modifies_known_mutable({}, "clear")
+    True
+    >>> modifies_known_mutable({}, "keys")
+    False
+    >>> modifies_known_mutable([], "append")
+    True
+    >>> modifies_known_mutable([], "index")
+    False
+
+    If called with an unsupported object, ``False`` is returned.
+
+    >>> modifies_known_mutable("foo", "upper")
+    False
+    """
+    for typespec, unsafe in _mutable_spec:
+        if isinstance(obj, typespec):
+            return attr in unsafe
+    return False
+
+
+class SandboxedEnvironment(Environment):
+    """The sandboxed environment.  It works like the regular environment but
+    tells the compiler to generate sandboxed code.  Additionally subclasses of
+    this environment may override the methods that tell the runtime what
+    attributes or functions are safe to access.
+
+    If the template tries to access insecure code a :exc:`SecurityError` is
+    raised.  However also other exceptions may occur during the rendering so
+    the caller has to ensure that all exceptions are caught.
+    """
+
+    sandboxed = True
+
+    #: default callback table for the binary operators.  A copy of this is
+    #: available on each instance of a sandboxed environment as
+    #: :attr:`binop_table`
+    default_binop_table: t.Dict[str, t.Callable[[t.Any, t.Any], t.Any]] = {
+        "+": operator.add,
+        "-": operator.sub,
+        "*": operator.mul,
+        "/": operator.truediv,
+        "//": operator.floordiv,
+        "**": operator.pow,
+        "%": operator.mod,
+    }
+
+    #: default callback table for the unary operators.  A copy of this is
+    #: available on each instance of a sandboxed environment as
+    #: :attr:`unop_table`
+    default_unop_table: t.Dict[str, t.Callable[[t.Any], t.Any]] = {
+        "+": operator.pos,
+        "-": operator.neg,
+    }
+
+    #: a set of binary operators that should be intercepted.  Each operator
+    #: that is added to this set (empty by default) is delegated to the
+    #: :meth:`call_binop` method that will perform the operator.  The default
+    #: operator callback is specified by :attr:`binop_table`.
+    #:
+    #: The following binary operators are interceptable:
+    #: ``//``, ``%``, ``+``, ``*``, ``-``, ``/``, and ``**``
+    #:
+    #: The default operation form the operator table corresponds to the
+    #: builtin function.  Intercepted calls are always slower than the native
+    #: operator call, so make sure only to intercept the ones you are
+    #: interested in.
+    #:
+    #: .. versionadded:: 2.6
+    intercepted_binops: t.FrozenSet[str] = frozenset()
+
+    #: a set of unary operators that should be intercepted.  Each operator
+    #: that is added to this set (empty by default) is delegated to the
+    #: :meth:`call_unop` method that will perform the operator.  The default
+    #: operator callback is specified by :attr:`unop_table`.
+    #:
+    #: The following unary operators are interceptable: ``+``, ``-``
+    #:
+    #: The default operation form the operator table corresponds to the
+    #: builtin function.  Intercepted calls are always slower than the native
+    #: operator call, so make sure only to intercept the ones you are
+    #: interested in.
+    #:
+    #: .. versionadded:: 2.6
+    intercepted_unops: t.FrozenSet[str] = frozenset()
+
+    def __init__(self, *args: t.Any, **kwargs: t.Any) -> None:
+        super().__init__(*args, **kwargs)
+        self.globals["range"] = safe_range
+        self.binop_table = self.default_binop_table.copy()
+        self.unop_table = self.default_unop_table.copy()
+
+    def is_safe_attribute(self, obj: t.Any, attr: str, value: t.Any) -> bool:
+        """The sandboxed environment will call this method to check if the
+        attribute of an object is safe to access.  Per default all attributes
+        starting with an underscore are considered private as well as the
+        special attributes of internal python objects as returned by the
+        :func:`is_internal_attribute` function.
+        """
+        return not (attr.startswith("_") or is_internal_attribute(obj, attr))
+
+    def is_safe_callable(self, obj: t.Any) -> bool:
+        """Check if an object is safely callable. By default callables
+        are considered safe unless decorated with :func:`unsafe`.
+
+        This also recognizes the Django convention of setting
+        ``func.alters_data = True``.
+        """
+        return not (
+            getattr(obj, "unsafe_callable", False) or getattr(obj, "alters_data", False)
+        )
+
+    def call_binop(
+        self, context: Context, operator: str, left: t.Any, right: t.Any
+    ) -> t.Any:
+        """For intercepted binary operator calls (:meth:`intercepted_binops`)
+        this function is executed instead of the builtin operator.  This can
+        be used to fine tune the behavior of certain operators.
+
+        .. versionadded:: 2.6
+        """
+        return self.binop_table[operator](left, right)
+
+    def call_unop(self, context: Context, operator: str, arg: t.Any) -> t.Any:
+        """For intercepted unary operator calls (:meth:`intercepted_unops`)
+        this function is executed instead of the builtin operator.  This can
+        be used to fine tune the behavior of certain operators.
+
+        .. versionadded:: 2.6
+        """
+        return self.unop_table[operator](arg)
+
+    def getitem(
+        self, obj: t.Any, argument: t.Union[str, t.Any]
+    ) -> t.Union[t.Any, Undefined]:
+        """Subscribe an object from sandboxed code."""
+        try:
+            return obj[argument]
+        except (TypeError, LookupError):
+            if isinstance(argument, str):
+                try:
+                    attr = str(argument)
+                except Exception:
+                    pass
+                else:
+                    try:
+                        value = getattr(obj, attr)
+                    except AttributeError:
+                        pass
+                    else:
+                        if self.is_safe_attribute(obj, argument, value):
+                            return value
+                        return self.unsafe_undefined(obj, argument)
+        return self.undefined(obj=obj, name=argument)
+
+    def getattr(self, obj: t.Any, attribute: str) -> t.Union[t.Any, Undefined]:
+        """Subscribe an object from sandboxed code and prefer the
+        attribute.  The attribute passed *must* be a bytestring.
+        """
+        try:
+            value = getattr(obj, attribute)
+        except AttributeError:
+            try:
+                return obj[attribute]
+            except (TypeError, LookupError):
+                pass
+        else:
+            if self.is_safe_attribute(obj, attribute, value):
+                return value
+            return self.unsafe_undefined(obj, attribute)
+        return self.undefined(obj=obj, name=attribute)
+
+    def unsafe_undefined(self, obj: t.Any, attribute: str) -> Undefined:
+        """Return an undefined object for unsafe attributes."""
+        return self.undefined(
+            f"access to attribute {attribute!r} of"
+            f" {type(obj).__name__!r} object is unsafe.",
+            name=attribute,
+            obj=obj,
+            exc=SecurityError,
+        )
+
+    def format_string(
+        self,
+        s: str,
+        args: t.Tuple[t.Any, ...],
+        kwargs: t.Dict[str, t.Any],
+        format_func: t.Optional[t.Callable] = None,
+    ) -> str:
+        """If a format call is detected, then this is routed through this
+        method so that our safety sandbox can be used for it.
+        """
+        formatter: SandboxedFormatter
+        if isinstance(s, Markup):
+            formatter = SandboxedEscapeFormatter(self, escape=s.escape)
+        else:
+            formatter = SandboxedFormatter(self)
+
+        if format_func is not None and format_func.__name__ == "format_map":
+            if len(args) != 1 or kwargs:
+                raise TypeError(
+                    "format_map() takes exactly one argument"
+                    f" {len(args) + (kwargs is not None)} given"
+                )
+
+            kwargs = args[0]
+            args = ()
+
+        rv = formatter.vformat(s, args, kwargs)
+        return type(s)(rv)
+
+    def call(
+        __self,  # noqa: B902
+        __context: Context,
+        __obj: t.Any,
+        *args: t.Any,
+        **kwargs: t.Any,
+    ) -> t.Any:
+        """Call an object from sandboxed code."""
+        fmt = inspect_format_method(__obj)
+        if fmt is not None:
+            return __self.format_string(fmt, args, kwargs, __obj)
+
+        # the double prefixes are to avoid double keyword argument
+        # errors when proxying the call.
+        if not __self.is_safe_callable(__obj):
+            raise SecurityError(f"{__obj!r} is not safely callable")
+        return __context.call(__obj, *args, **kwargs)
+
+
+class ImmutableSandboxedEnvironment(SandboxedEnvironment):
+    """Works exactly like the regular `SandboxedEnvironment` but does not
+    permit modifications on the builtin mutable objects `list`, `set`, and
+    `dict` by using the :func:`modifies_known_mutable` function.
+    """
+
+    def is_safe_attribute(self, obj: t.Any, attr: str, value: t.Any) -> bool:
+        if not super().is_safe_attribute(obj, attr, value):
+            return False
+
+        return not modifies_known_mutable(obj, attr)
+
+
+class SandboxedFormatter(Formatter):
+    def __init__(self, env: Environment, **kwargs: t.Any) -> None:
+        self._env = env
+        super().__init__(**kwargs)  # type: ignore
+
+    def get_field(
+        self, field_name: str, args: t.Sequence[t.Any], kwargs: t.Mapping[str, t.Any]
+    ) -> t.Tuple[t.Any, str]:
+        first, rest = formatter_field_name_split(field_name)
+        obj = self.get_value(first, args, kwargs)
+        for is_attr, i in rest:
+            if is_attr:
+                obj = self._env.getattr(obj, i)
+            else:
+                obj = self._env.getitem(obj, i)
+        return obj, first
+
+
+class SandboxedEscapeFormatter(SandboxedFormatter, EscapeFormatter):
+    pass

lib/spack/external/_vendoring/jinja2/tests.py

@@ -0,0 +1,255 @@
+"""Built-in template tests used with the ``is`` operator."""
+import operator
+import typing as t
+from collections import abc
+from numbers import Number
+
+from .runtime import Undefined
+from .utils import pass_environment
+
+if t.TYPE_CHECKING:
+    from .environment import Environment
+
+
+def test_odd(value: int) -> bool:
+    """Return true if the variable is odd."""
+    return value % 2 == 1
+
+
+def test_even(value: int) -> bool:
+    """Return true if the variable is even."""
+    return value % 2 == 0
+
+
+def test_divisibleby(value: int, num: int) -> bool:
+    """Check if a variable is divisible by a number."""
+    return value % num == 0
+
+
+def test_defined(value: t.Any) -> bool:
+    """Return true if the variable is defined:
+
+    .. sourcecode:: jinja
+
+        {% if variable is defined %}
+            value of variable: {{ variable }}
+        {% else %}
+            variable is not defined
+        {% endif %}
+
+    See the :func:`default` filter for a simple way to set undefined
+    variables.
+    """
+    return not isinstance(value, Undefined)
+
+
+def test_undefined(value: t.Any) -> bool:
+    """Like :func:`defined` but the other way round."""
+    return isinstance(value, Undefined)
+
+
+@pass_environment
+def test_filter(env: "Environment", value: str) -> bool:
+    """Check if a filter exists by name. Useful if a filter may be
+    optionally available.
+
+    .. code-block:: jinja
+
+        {% if 'markdown' is filter %}
+            {{ value | markdown }}
+        {% else %}
+            {{ value }}
+        {% endif %}
+
+    .. versionadded:: 3.0
+    """
+    return value in env.filters
+
+
+@pass_environment
+def test_test(env: "Environment", value: str) -> bool:
+    """Check if a test exists by name. Useful if a test may be
+    optionally available.
+
+    .. code-block:: jinja
+
+        {% if 'loud' is test %}
+            {% if value is loud %}
+                {{ value|upper }}
+            {% else %}
+                {{ value|lower }}
+            {% endif %}
+        {% else %}
+            {{ value }}
+        {% endif %}
+
+    .. versionadded:: 3.0
+    """
+    return value in env.tests
+
+
+def test_none(value: t.Any) -> bool:
+    """Return true if the variable is none."""
+    return value is None
+
+
+def test_boolean(value: t.Any) -> bool:
+    """Return true if the object is a boolean value.
+
+    .. versionadded:: 2.11
+    """
+    return value is True or value is False
+
+
+def test_false(value: t.Any) -> bool:
+    """Return true if the object is False.
+
+    .. versionadded:: 2.11
+    """
+    return value is False
+
+
+def test_true(value: t.Any) -> bool:
+    """Return true if the object is True.
+
+    .. versionadded:: 2.11
+    """
+    return value is True
+
+
+# NOTE: The existing 'number' test matches booleans and floats
+def test_integer(value: t.Any) -> bool:
+    """Return true if the object is an integer.
+
+    .. versionadded:: 2.11
+    """
+    return isinstance(value, int) and value is not True and value is not False
+
+
+# NOTE: The existing 'number' test matches booleans and integers
+def test_float(value: t.Any) -> bool:
+    """Return true if the object is a float.
+
+    .. versionadded:: 2.11
+    """
+    return isinstance(value, float)
+
+
+def test_lower(value: str) -> bool:
+    """Return true if the variable is lowercased."""
+    return str(value).islower()
+
+
+def test_upper(value: str) -> bool:
+    """Return true if the variable is uppercased."""
+    return str(value).isupper()
+
+
+def test_string(value: t.Any) -> bool:
+    """Return true if the object is a string."""
+    return isinstance(value, str)
+
+
+def test_mapping(value: t.Any) -> bool:
+    """Return true if the object is a mapping (dict etc.).
+
+    .. versionadded:: 2.6
+    """
+    return isinstance(value, abc.Mapping)
+
+
+def test_number(value: t.Any) -> bool:
+    """Return true if the variable is a number."""
+    return isinstance(value, Number)
+
+
+def test_sequence(value: t.Any) -> bool:
+    """Return true if the variable is a sequence. Sequences are variables
+    that are iterable.
+    """
+    try:
+        len(value)
+        value.__getitem__
+    except Exception:
+        return False
+
+    return True
+
+
+def test_sameas(value: t.Any, other: t.Any) -> bool:
+    """Check if an object points to the same memory address than another
+    object:
+
+    .. sourcecode:: jinja
+
+        {% if foo.attribute is sameas false %}
+            the foo attribute really is the `False` singleton
+        {% endif %}
+    """
+    return value is other
+
+
+def test_iterable(value: t.Any) -> bool:
+    """Check if it's possible to iterate over an object."""
+    try:
+        iter(value)
+    except TypeError:
+        return False
+
+    return True
+
+
+def test_escaped(value: t.Any) -> bool:
+    """Check if the value is escaped."""
+    return hasattr(value, "__html__")
+
+
+def test_in(value: t.Any, seq: t.Container) -> bool:
+    """Check if value is in seq.
+
+    .. versionadded:: 2.10
+    """
+    return value in seq
+
+
+TESTS = {
+    "odd": test_odd,
+    "even": test_even,
+    "divisibleby": test_divisibleby,
+    "defined": test_defined,
+    "undefined": test_undefined,
+    "filter": test_filter,
+    "test": test_test,
+    "none": test_none,
+    "boolean": test_boolean,
+    "false": test_false,
+    "true": test_true,
+    "integer": test_integer,
+    "float": test_float,
+    "lower": test_lower,
+    "upper": test_upper,
+    "string": test_string,
+    "mapping": test_mapping,
+    "number": test_number,
+    "sequence": test_sequence,
+    "iterable": test_iterable,
+    "callable": callable,
+    "sameas": test_sameas,
+    "escaped": test_escaped,
+    "in": test_in,
+    "==": operator.eq,
+    "eq": operator.eq,
+    "equalto": operator.eq,
+    "!=": operator.ne,
+    "ne": operator.ne,
+    ">": operator.gt,
+    "gt": operator.gt,
+    "greaterthan": operator.gt,
+    "ge": operator.ge,
+    ">=": operator.ge,
+    "<": operator.lt,
+    "lt": operator.lt,
+    "lessthan": operator.lt,
+    "<=": operator.le,
+    "le": operator.le,
+}

lib/spack/external/_vendoring/jinja2/utils.py

@@ -0,0 +1,854 @@
+import enum
+import json
+import os
+import re
+import typing as t
+import warnings
+from collections import abc
+from collections import deque
+from random import choice
+from random import randrange
+from threading import Lock
+from types import CodeType
+from urllib.parse import quote_from_bytes
+
+import markupsafe
+
+if t.TYPE_CHECKING:
+    import typing_extensions as te
+
+F = t.TypeVar("F", bound=t.Callable[..., t.Any])
+
+# special singleton representing missing values for the runtime
+missing: t.Any = type("MissingType", (), {"__repr__": lambda x: "missing"})()
+
+internal_code: t.MutableSet[CodeType] = set()
+
+concat = "".join
+
+
+def pass_context(f: F) -> F:
+    """Pass the :class:`~jinja2.runtime.Context` as the first argument
+    to the decorated function when called while rendering a template.
+
+    Can be used on functions, filters, and tests.
+
+    If only ``Context.eval_context`` is needed, use
+    :func:`pass_eval_context`. If only ``Context.environment`` is
+    needed, use :func:`pass_environment`.
+
+    .. versionadded:: 3.0.0
+        Replaces ``contextfunction`` and ``contextfilter``.
+    """
+    f.jinja_pass_arg = _PassArg.context  # type: ignore
+    return f
+
+
+def pass_eval_context(f: F) -> F:
+    """Pass the :class:`~jinja2.nodes.EvalContext` as the first argument
+    to the decorated function when called while rendering a template.
+    See :ref:`eval-context`.
+
+    Can be used on functions, filters, and tests.
+
+    If only ``EvalContext.environment`` is needed, use
+    :func:`pass_environment`.
+
+    .. versionadded:: 3.0.0
+        Replaces ``evalcontextfunction`` and ``evalcontextfilter``.
+    """
+    f.jinja_pass_arg = _PassArg.eval_context  # type: ignore
+    return f
+
+
+def pass_environment(f: F) -> F:
+    """Pass the :class:`~jinja2.Environment` as the first argument to
+    the decorated function when called while rendering a template.
+
+    Can be used on functions, filters, and tests.
+
+    .. versionadded:: 3.0.0
+        Replaces ``environmentfunction`` and ``environmentfilter``.
+    """
+    f.jinja_pass_arg = _PassArg.environment  # type: ignore
+    return f
+
+
+class _PassArg(enum.Enum):
+    context = enum.auto()
+    eval_context = enum.auto()
+    environment = enum.auto()
+
+    @classmethod
+    def from_obj(cls, obj: F) -> t.Optional["_PassArg"]:
+        if hasattr(obj, "jinja_pass_arg"):
+            return obj.jinja_pass_arg  # type: ignore
+
+        for prefix in "context", "eval_context", "environment":
+            squashed = prefix.replace("_", "")
+
+            for name in f"{squashed}function", f"{squashed}filter":
+                if getattr(obj, name, False) is True:
+                    warnings.warn(
+                        f"{name!r} is deprecated and will stop working"
+                        f" in Jinja 3.1. Use 'pass_{prefix}' instead.",
+                        DeprecationWarning,
+                        stacklevel=2,
+                    )
+                    return cls[prefix]
+
+        return None
+
+
+def contextfunction(f: F) -> F:
+    """Pass the context as the first argument to the decorated function.
+
+    .. deprecated:: 3.0
+        Will be removed in Jinja 3.1. Use :func:`~jinja2.pass_context`
+        instead.
+    """
+    warnings.warn(
+        "'contextfunction' is renamed to 'pass_context', the old name"
+        " will be removed in Jinja 3.1.",
+        DeprecationWarning,
+        stacklevel=2,
+    )
+    return pass_context(f)
+
+
+def evalcontextfunction(f: F) -> F:
+    """Pass the eval context as the first argument to the decorated
+    function.
+
+    .. deprecated:: 3.0
+        Will be removed in Jinja 3.1. Use
+        :func:`~jinja2.pass_eval_context` instead.
+
+    .. versionadded:: 2.4
+    """
+    warnings.warn(
+        "'evalcontextfunction' is renamed to 'pass_eval_context', the"
+        " old name will be removed in Jinja 3.1.",
+        DeprecationWarning,
+        stacklevel=2,
+    )
+    return pass_eval_context(f)
+
+
+def environmentfunction(f: F) -> F:
+    """Pass the environment as the first argument to the decorated
+    function.
+
+    .. deprecated:: 3.0
+        Will be removed in Jinja 3.1. Use
+        :func:`~jinja2.pass_environment` instead.
+    """
+    warnings.warn(
+        "'environmentfunction' is renamed to 'pass_environment', the"
+        " old name will be removed in Jinja 3.1.",
+        DeprecationWarning,
+        stacklevel=2,
+    )
+    return pass_environment(f)
+
+
+def internalcode(f: F) -> F:
+    """Marks the function as internally used"""
+    internal_code.add(f.__code__)
+    return f
+
+
+def is_undefined(obj: t.Any) -> bool:
+    """Check if the object passed is undefined.  This does nothing more than
+    performing an instance check against :class:`Undefined` but looks nicer.
+    This can be used for custom filters or tests that want to react to
+    undefined variables.  For example a custom default filter can look like
+    this::
+
+        def default(var, default=''):
+            if is_undefined(var):
+                return default
+            return var
+    """
+    from .runtime import Undefined
+
+    return isinstance(obj, Undefined)
+
+
+def consume(iterable: t.Iterable[t.Any]) -> None:
+    """Consumes an iterable without doing anything with it."""
+    for _ in iterable:
+        pass
+
+
+def clear_caches() -> None:
+    """Jinja keeps internal caches for environments and lexers.  These are
+    used so that Jinja doesn't have to recreate environments and lexers all
+    the time.  Normally you don't have to care about that but if you are
+    measuring memory consumption you may want to clean the caches.
+    """
+    from .environment import get_spontaneous_environment
+    from .lexer import _lexer_cache
+
+    get_spontaneous_environment.cache_clear()
+    _lexer_cache.clear()
+
+
+def import_string(import_name: str, silent: bool = False) -> t.Any:
+    """Imports an object based on a string.  This is useful if you want to
+    use import paths as endpoints or something similar.  An import path can
+    be specified either in dotted notation (``xml.sax.saxutils.escape``)
+    or with a colon as object delimiter (``xml.sax.saxutils:escape``).
+
+    If the `silent` is True the return value will be `None` if the import
+    fails.
+
+    :return: imported object
+    """
+    try:
+        if ":" in import_name:
+            module, obj = import_name.split(":", 1)
+        elif "." in import_name:
+            module, _, obj = import_name.rpartition(".")
+        else:
+            return __import__(import_name)
+        return getattr(__import__(module, None, None, [obj]), obj)
+    except (ImportError, AttributeError):
+        if not silent:
+            raise
+
+
+def open_if_exists(filename: str, mode: str = "rb") -> t.Optional[t.IO]:
+    """Returns a file descriptor for the filename if that file exists,
+    otherwise ``None``.
+    """
+    if not os.path.isfile(filename):
+        return None
+
+    return open(filename, mode)
+
+
+def object_type_repr(obj: t.Any) -> str:
+    """Returns the name of the object's type.  For some recognized
+    singletons the name of the object is returned instead. (For
+    example for `None` and `Ellipsis`).
+    """
+    if obj is None:
+        return "None"
+    elif obj is Ellipsis:
+        return "Ellipsis"
+
+    cls = type(obj)
+
+    if cls.__module__ == "builtins":
+        return f"{cls.__name__} object"
+
+    return f"{cls.__module__}.{cls.__name__} object"
+
+
+def pformat(obj: t.Any) -> str:
+    """Format an object using :func:`pprint.pformat`."""
+    from pprint import pformat  # type: ignore
+
+    return pformat(obj)
+
+
+_http_re = re.compile(
+    r"""
+    ^
+    (
+        (https?://|www\.)  # scheme or www
+        (([\w%-]+\.)+)?  # subdomain
+        (
+            [a-z]{2,63}  # basic tld
+        |
+            xn--[\w%]{2,59}  # idna tld
+        )
+    |
+        ([\w%-]{2,63}\.)+  # basic domain
+        (com|net|int|edu|gov|org|info|mil)  # basic tld
+    |
+        (https?://)  # scheme
+        (
+            (([\d]{1,3})(\.[\d]{1,3}){3})  # IPv4
+        |
+            (\[([\da-f]{0,4}:){2}([\da-f]{0,4}:?){1,6}])  # IPv6
+        )
+    )
+    (?::[\d]{1,5})?  # port
+    (?:[/?#]\S*)?  # path, query, and fragment
+    $
+    """,
+    re.IGNORECASE | re.VERBOSE,
+)
+_email_re = re.compile(r"^\S+@\w[\w.-]*\.\w+$")
+
+
+def urlize(
+    text: str,
+    trim_url_limit: t.Optional[int] = None,
+    rel: t.Optional[str] = None,
+    target: t.Optional[str] = None,
+    extra_schemes: t.Optional[t.Iterable[str]] = None,
+) -> str:
+    """Convert URLs in text into clickable links.
+
+    This may not recognize links in some situations. Usually, a more
+    comprehensive formatter, such as a Markdown library, is a better
+    choice.
+
+    Works on ``http://``, ``https://``, ``www.``, ``mailto:``, and email
+    addresses. Links with trailing punctuation (periods, commas, closing
+    parentheses) and leading punctuation (opening parentheses) are
+    recognized excluding the punctuation. Email addresses that include
+    header fields are not recognized (for example,
+    ``mailto:address@example.com?cc=copy@example.com``).
+
+    :param text: Original text containing URLs to link.
+    :param trim_url_limit: Shorten displayed URL values to this length.
+    :param target: Add the ``target`` attribute to links.
+    :param rel: Add the ``rel`` attribute to links.
+    :param extra_schemes: Recognize URLs that start with these schemes
+        in addition to the default behavior.
+
+    .. versionchanged:: 3.0
+        The ``extra_schemes`` parameter was added.
+
+    .. versionchanged:: 3.0
+        Generate ``https://`` links for URLs without a scheme.
+
+    .. versionchanged:: 3.0
+        The parsing rules were updated. Recognize email addresses with
+        or without the ``mailto:`` scheme. Validate IP addresses. Ignore
+        parentheses and brackets in more cases.
+    """
+    if trim_url_limit is not None:
+
+        def trim_url(x: str) -> str:
+            if len(x) > trim_url_limit:  # type: ignore
+                return f"{x[:trim_url_limit]}..."
+
+            return x
+
+    else:
+
+        def trim_url(x: str) -> str:
+            return x
+
+    words = re.split(r"(\s+)", str(markupsafe.escape(text)))
+    rel_attr = f' rel="{markupsafe.escape(rel)}"' if rel else ""
+    target_attr = f' target="{markupsafe.escape(target)}"' if target else ""
+
+    for i, word in enumerate(words):
+        head, middle, tail = "", word, ""
+        match = re.match(r"^([(<]|&lt;)+", middle)
+
+        if match:
+            head = match.group()
+            middle = middle[match.end() :]
+
+        # Unlike lead, which is anchored to the start of the string,
+        # need to check that the string ends with any of the characters
+        # before trying to match all of them, to avoid backtracking.
+        if middle.endswith((")", ">", ".", ",", "\n", "&gt;")):
+            match = re.search(r"([)>.,\n]|&gt;)+$", middle)
+
+            if match:
+                tail = match.group()
+                middle = middle[: match.start()]
+
+        # Prefer balancing parentheses in URLs instead of ignoring a
+        # trailing character.
+        for start_char, end_char in ("(", ")"), ("<", ">"), ("&lt;", "&gt;"):
+            start_count = middle.count(start_char)
+
+            if start_count <= middle.count(end_char):
+                # Balanced, or lighter on the left
+                continue
+
+            # Move as many as possible from the tail to balance
+            for _ in range(min(start_count, tail.count(end_char))):
+                end_index = tail.index(end_char) + len(end_char)
+                # Move anything in the tail before the end char too
+                middle += tail[:end_index]
+                tail = tail[end_index:]
+
+        if _http_re.match(middle):
+            if middle.startswith("https://") or middle.startswith("http://"):
+                middle = (
+                    f'<a href="{middle}"{rel_attr}{target_attr}>{trim_url(middle)}</a>'
+                )
+            else:
+                middle = (
+                    f'<a href="https://{middle}"{rel_attr}{target_attr}>'
+                    f"{trim_url(middle)}</a>"
+                )
+
+        elif middle.startswith("mailto:") and _email_re.match(middle[7:]):
+            middle = f'<a href="{middle}">{middle[7:]}</a>'
+
+        elif (
+            "@" in middle
+            and not middle.startswith("www.")
+            and ":" not in middle
+            and _email_re.match(middle)
+        ):
+            middle = f'<a href="mailto:{middle}">{middle}</a>'
+
+        elif extra_schemes is not None:
+            for scheme in extra_schemes:
+                if middle != scheme and middle.startswith(scheme):
+                    middle = f'<a href="{middle}"{rel_attr}{target_attr}>{middle}</a>'
+
+        words[i] = f"{head}{middle}{tail}"
+
+    return "".join(words)
+
+
+def generate_lorem_ipsum(
+    n: int = 5, html: bool = True, min: int = 20, max: int = 100
+) -> str:
+    """Generate some lorem ipsum for the template."""
+    from .constants import LOREM_IPSUM_WORDS
+
+    words = LOREM_IPSUM_WORDS.split()
+    result = []
+
+    for _ in range(n):
+        next_capitalized = True
+        last_comma = last_fullstop = 0
+        word = None
+        last = None
+        p = []
+
+        # each paragraph contains out of 20 to 100 words.
+        for idx, _ in enumerate(range(randrange(min, max))):
+            while True:
+                word = choice(words)
+                if word != last:
+                    last = word
+                    break
+            if next_capitalized:
+                word = word.capitalize()
+                next_capitalized = False
+            # add commas
+            if idx - randrange(3, 8) > last_comma:
+                last_comma = idx
+                last_fullstop += 2
+                word += ","
+            # add end of sentences
+            if idx - randrange(10, 20) > last_fullstop:
+                last_comma = last_fullstop = idx
+                word += "."
+                next_capitalized = True
+            p.append(word)
+
+        # ensure that the paragraph ends with a dot.
+        p_str = " ".join(p)
+
+        if p_str.endswith(","):
+            p_str = p_str[:-1] + "."
+        elif not p_str.endswith("."):
+            p_str += "."
+
+        result.append(p_str)
+
+    if not html:
+        return "\n\n".join(result)
+    return markupsafe.Markup(
+        "\n".join(f"<p>{markupsafe.escape(x)}</p>" for x in result)
+    )
+
+
+def url_quote(obj: t.Any, charset: str = "utf-8", for_qs: bool = False) -> str:
+    """Quote a string for use in a URL using the given charset.
+
+    :param obj: String or bytes to quote. Other types are converted to
+        string then encoded to bytes using the given charset.
+    :param charset: Encode text to bytes using this charset.
+    :param for_qs: Quote "/" and use "+" for spaces.
+    """
+    if not isinstance(obj, bytes):
+        if not isinstance(obj, str):
+            obj = str(obj)
+
+        obj = obj.encode(charset)
+
+    safe = b"" if for_qs else b"/"
+    rv = quote_from_bytes(obj, safe)
+
+    if for_qs:
+        rv = rv.replace("%20", "+")
+
+    return rv
+
+
+def unicode_urlencode(obj: t.Any, charset: str = "utf-8", for_qs: bool = False) -> str:
+    import warnings
+
+    warnings.warn(
+        "'unicode_urlencode' has been renamed to 'url_quote'. The old"
+        " name will be removed in Jinja 3.1.",
+        DeprecationWarning,
+        stacklevel=2,
+    )
+    return url_quote(obj, charset=charset, for_qs=for_qs)
+
+
+@abc.MutableMapping.register
+class LRUCache:
+    """A simple LRU Cache implementation."""
+
+    # this is fast for small capacities (something below 1000) but doesn't
+    # scale.  But as long as it's only used as storage for templates this
+    # won't do any harm.
+
+    def __init__(self, capacity: int) -> None:
+        self.capacity = capacity
+        self._mapping: t.Dict[t.Any, t.Any] = {}
+        self._queue: "te.Deque[t.Any]" = deque()
+        self._postinit()
+
+    def _postinit(self) -> None:
+        # alias all queue methods for faster lookup
+        self._popleft = self._queue.popleft
+        self._pop = self._queue.pop
+        self._remove = self._queue.remove
+        self._wlock = Lock()
+        self._append = self._queue.append
+
+    def __getstate__(self) -> t.Mapping[str, t.Any]:
+        return {
+            "capacity": self.capacity,
+            "_mapping": self._mapping,
+            "_queue": self._queue,
+        }
+
+    def __setstate__(self, d: t.Mapping[str, t.Any]) -> None:
+        self.__dict__.update(d)
+        self._postinit()
+
+    def __getnewargs__(self) -> t.Tuple:
+        return (self.capacity,)
+
+    def copy(self) -> "LRUCache":
+        """Return a shallow copy of the instance."""
+        rv = self.__class__(self.capacity)
+        rv._mapping.update(self._mapping)
+        rv._queue.extend(self._queue)
+        return rv
+
+    def get(self, key: t.Any, default: t.Any = None) -> t.Any:
+        """Return an item from the cache dict or `default`"""
+        try:
+            return self[key]
+        except KeyError:
+            return default
+
+    def setdefault(self, key: t.Any, default: t.Any = None) -> t.Any:
+        """Set `default` if the key is not in the cache otherwise
+        leave unchanged. Return the value of this key.
+        """
+        try:
+            return self[key]
+        except KeyError:
+            self[key] = default
+            return default
+
+    def clear(self) -> None:
+        """Clear the cache."""
+        with self._wlock:
+            self._mapping.clear()
+            self._queue.clear()
+
+    def __contains__(self, key: t.Any) -> bool:
+        """Check if a key exists in this cache."""
+        return key in self._mapping
+
+    def __len__(self) -> int:
+        """Return the current size of the cache."""
+        return len(self._mapping)
+
+    def __repr__(self) -> str:
+        return f"<{type(self).__name__} {self._mapping!r}>"
+
+    def __getitem__(self, key: t.Any) -> t.Any:
+        """Get an item from the cache. Moves the item up so that it has the
+        highest priority then.
+
+        Raise a `KeyError` if it does not exist.
+        """
+        with self._wlock:
+            rv = self._mapping[key]
+
+            if self._queue[-1] != key:
+                try:
+                    self._remove(key)
+                except ValueError:
+                    # if something removed the key from the container
+                    # when we read, ignore the ValueError that we would
+                    # get otherwise.
+                    pass
+
+                self._append(key)
+
+            return rv
+
+    def __setitem__(self, key: t.Any, value: t.Any) -> None:
+        """Sets the value for an item. Moves the item up so that it
+        has the highest priority then.
+        """
+        with self._wlock:
+            if key in self._mapping:
+                self._remove(key)
+            elif len(self._mapping) == self.capacity:
+                del self._mapping[self._popleft()]
+
+            self._append(key)
+            self._mapping[key] = value
+
+    def __delitem__(self, key: t.Any) -> None:
+        """Remove an item from the cache dict.
+        Raise a `KeyError` if it does not exist.
+        """
+        with self._wlock:
+            del self._mapping[key]
+
+            try:
+                self._remove(key)
+            except ValueError:
+                pass
+
+    def items(self) -> t.Iterable[t.Tuple[t.Any, t.Any]]:
+        """Return a list of items."""
+        result = [(key, self._mapping[key]) for key in list(self._queue)]
+        result.reverse()
+        return result
+
+    def values(self) -> t.Iterable[t.Any]:
+        """Return a list of all values."""
+        return [x[1] for x in self.items()]
+
+    def keys(self) -> t.Iterable[t.Any]:
+        """Return a list of all keys ordered by most recent usage."""
+        return list(self)
+
+    def __iter__(self) -> t.Iterator[t.Any]:
+        return reversed(tuple(self._queue))
+
+    def __reversed__(self) -> t.Iterator[t.Any]:
+        """Iterate over the keys in the cache dict, oldest items
+        coming first.
+        """
+        return iter(tuple(self._queue))
+
+    __copy__ = copy
+
+
+def select_autoescape(
+    enabled_extensions: t.Collection[str] = ("html", "htm", "xml"),
+    disabled_extensions: t.Collection[str] = (),
+    default_for_string: bool = True,
+    default: bool = False,
+) -> t.Callable[[t.Optional[str]], bool]:
+    """Intelligently sets the initial value of autoescaping based on the
+    filename of the template.  This is the recommended way to configure
+    autoescaping if you do not want to write a custom function yourself.
+
+    If you want to enable it for all templates created from strings or
+    for all templates with `.html` and `.xml` extensions::
+
+        from jinja2 import Environment, select_autoescape
+        env = Environment(autoescape=select_autoescape(
+            enabled_extensions=('html', 'xml'),
+            default_for_string=True,
+        ))
+
+    Example configuration to turn it on at all times except if the template
+    ends with `.txt`::
+
+        from jinja2 import Environment, select_autoescape
+        env = Environment(autoescape=select_autoescape(
+            disabled_extensions=('txt',),
+            default_for_string=True,
+            default=True,
+        ))
+
+    The `enabled_extensions` is an iterable of all the extensions that
+    autoescaping should be enabled for.  Likewise `disabled_extensions` is
+    a list of all templates it should be disabled for.  If a template is
+    loaded from a string then the default from `default_for_string` is used.
+    If nothing matches then the initial value of autoescaping is set to the
+    value of `default`.
+
+    For security reasons this function operates case insensitive.
+
+    .. versionadded:: 2.9
+    """
+    enabled_patterns = tuple(f".{x.lstrip('.').lower()}" for x in enabled_extensions)
+    disabled_patterns = tuple(f".{x.lstrip('.').lower()}" for x in disabled_extensions)
+
+    def autoescape(template_name: t.Optional[str]) -> bool:
+        if template_name is None:
+            return default_for_string
+        template_name = template_name.lower()
+        if template_name.endswith(enabled_patterns):
+            return True
+        if template_name.endswith(disabled_patterns):
+            return False
+        return default
+
+    return autoescape
+
+
+def htmlsafe_json_dumps(
+    obj: t.Any, dumps: t.Optional[t.Callable[..., str]] = None, **kwargs: t.Any
+) -> markupsafe.Markup:
+    """Serialize an object to a string of JSON with :func:`json.dumps`,
+    then replace HTML-unsafe characters with Unicode escapes and mark
+    the result safe with :class:`~markupsafe.Markup`.
+
+    This is available in templates as the ``|tojson`` filter.
+
+    The following characters are escaped: ``<``, ``>``, ``&``, ``'``.
+
+    The returned string is safe to render in HTML documents and
+    ``<script>`` tags. The exception is in HTML attributes that are
+    double quoted; either use single quotes or the ``|forceescape``
+    filter.
+
+    :param obj: The object to serialize to JSON.
+    :param dumps: The ``dumps`` function to use. Defaults to
+        ``env.policies["json.dumps_function"]``, which defaults to
+        :func:`json.dumps`.
+    :param kwargs: Extra arguments to pass to ``dumps``. Merged onto
+        ``env.policies["json.dumps_kwargs"]``.
+
+    .. versionchanged:: 3.0
+        The ``dumper`` parameter is renamed to ``dumps``.
+
+    .. versionadded:: 2.9
+    """
+    if dumps is None:
+        dumps = json.dumps
+
+    return markupsafe.Markup(
+        dumps(obj, **kwargs)
+        .replace("<", "\\u003c")
+        .replace(">", "\\u003e")
+        .replace("&", "\\u0026")
+        .replace("'", "\\u0027")
+    )
+
+
+class Cycler:
+    """Cycle through values by yield them one at a time, then restarting
+    once the end is reached. Available as ``cycler`` in templates.
+
+    Similar to ``loop.cycle``, but can be used outside loops or across
+    multiple loops. For example, render a list of folders and files in a
+    list, alternating giving them "odd" and "even" classes.
+
+    .. code-block:: html+jinja
+
+        {% set row_class = cycler("odd", "even") %}
+        <ul class="browser">
+        {% for folder in folders %}
+          <li class="folder {{ row_class.next() }}">{{ folder }}
+        {% endfor %}
+        {% for file in files %}
+          <li class="file {{ row_class.next() }}">{{ file }}
+        {% endfor %}
+        </ul>
+
+    :param items: Each positional argument will be yielded in the order
+        given for each cycle.
+
+    .. versionadded:: 2.1
+    """
+
+    def __init__(self, *items: t.Any) -> None:
+        if not items:
+            raise RuntimeError("at least one item has to be provided")
+        self.items = items
+        self.pos = 0
+
+    def reset(self) -> None:
+        """Resets the current item to the first item."""
+        self.pos = 0
+
+    @property
+    def current(self) -> t.Any:
+        """Return the current item. Equivalent to the item that will be
+        returned next time :meth:`next` is called.
+        """
+        return self.items[self.pos]
+
+    def next(self) -> t.Any:
+        """Return the current item, then advance :attr:`current` to the
+        next item.
+        """
+        rv = self.current
+        self.pos = (self.pos + 1) % len(self.items)
+        return rv
+
+    __next__ = next
+
+
+class Joiner:
+    """A joining helper for templates."""
+
+    def __init__(self, sep: str = ", ") -> None:
+        self.sep = sep
+        self.used = False
+
+    def __call__(self) -> str:
+        if not self.used:
+            self.used = True
+            return ""
+        return self.sep
+
+
+class Namespace:
+    """A namespace object that can hold arbitrary attributes.  It may be
+    initialized from a dictionary or with keyword arguments."""
+
+    def __init__(*args: t.Any, **kwargs: t.Any) -> None:  # noqa: B902
+        self, args = args[0], args[1:]
+        self.__attrs = dict(*args, **kwargs)
+
+    def __getattribute__(self, name: str) -> t.Any:
+        # __class__ is needed for the awaitable check in async mode
+        if name in {"_Namespace__attrs", "__class__"}:
+            return object.__getattribute__(self, name)
+        try:
+            return self.__attrs[name]
+        except KeyError:
+            raise AttributeError(name) from None
+
+    def __setitem__(self, name: str, value: t.Any) -> None:
+        self.__attrs[name] = value
+
+    def __repr__(self) -> str:
+        return f"<Namespace {self.__attrs!r}>"
+
+
+class Markup(markupsafe.Markup):
+    def __new__(cls, base="", encoding=None, errors="strict"):  # type: ignore
+        warnings.warn(
+            "'jinja2.Markup' is deprecated and will be removed in Jinja"
+            " 3.1. Import 'markupsafe.Markup' instead.",
+            DeprecationWarning,
+            stacklevel=2,
+        )
+        return super().__new__(cls, base, encoding, errors)
+
+
+def escape(s: t.Any) -> str:
+    warnings.warn(
+        "'jinja2.escape' is deprecated and will be removed in Jinja"
+        " 3.1. Import 'markupsafe.escape' instead.",
+        DeprecationWarning,
+        stacklevel=2,
+    )
+    return markupsafe.escape(s)

lib/spack/external/_vendoring/jinja2/visitor.py

@@ -0,0 +1,92 @@
+"""API for traversing the AST nodes. Implemented by the compiler and
+meta introspection.
+"""
+import typing as t
+
+from .nodes import Node
+
+if t.TYPE_CHECKING:
+    import typing_extensions as te
+
+    class VisitCallable(te.Protocol):
+        def __call__(self, node: Node, *args: t.Any, **kwargs: t.Any) -> t.Any:
+            ...
+
+
+class NodeVisitor:
+    """Walks the abstract syntax tree and call visitor functions for every
+    node found.  The visitor functions may return values which will be
+    forwarded by the `visit` method.
+
+    Per default the visitor functions for the nodes are ``'visit_'`` +
+    class name of the node.  So a `TryFinally` node visit function would
+    be `visit_TryFinally`.  This behavior can be changed by overriding
+    the `get_visitor` function.  If no visitor function exists for a node
+    (return value `None`) the `generic_visit` visitor is used instead.
+    """
+
+    def get_visitor(self, node: Node) -> "t.Optional[VisitCallable]":
+        """Return the visitor function for this node or `None` if no visitor
+        exists for this node.  In that case the generic visit function is
+        used instead.
+        """
+        return getattr(self, f"visit_{type(node).__name__}", None)  # type: ignore
+
+    def visit(self, node: Node, *args: t.Any, **kwargs: t.Any) -> t.Any:
+        """Visit a node."""
+        f = self.get_visitor(node)
+
+        if f is not None:
+            return f(node, *args, **kwargs)
+
+        return self.generic_visit(node, *args, **kwargs)
+
+    def generic_visit(self, node: Node, *args: t.Any, **kwargs: t.Any) -> t.Any:
+        """Called if no explicit visitor function exists for a node."""
+        for node in node.iter_child_nodes():
+            self.visit(node, *args, **kwargs)
+
+
+class NodeTransformer(NodeVisitor):
+    """Walks the abstract syntax tree and allows modifications of nodes.
+
+    The `NodeTransformer` will walk the AST and use the return value of the
+    visitor functions to replace or remove the old node.  If the return
+    value of the visitor function is `None` the node will be removed
+    from the previous location otherwise it's replaced with the return
+    value.  The return value may be the original node in which case no
+    replacement takes place.
+    """
+
+    def generic_visit(self, node: Node, *args: t.Any, **kwargs: t.Any) -> Node:
+        for field, old_value in node.iter_fields():
+            if isinstance(old_value, list):
+                new_values = []
+                for value in old_value:
+                    if isinstance(value, Node):
+                        value = self.visit(value, *args, **kwargs)
+                        if value is None:
+                            continue
+                        elif not isinstance(value, Node):
+                            new_values.extend(value)
+                            continue
+                    new_values.append(value)
+                old_value[:] = new_values
+            elif isinstance(old_value, Node):
+                new_node = self.visit(old_value, *args, **kwargs)
+                if new_node is None:
+                    delattr(node, field)
+                else:
+                    setattr(node, field, new_node)
+        return node
+
+    def visit_list(self, node: Node, *args: t.Any, **kwargs: t.Any) -> t.List[Node]:
+        """As transformers may return lists in some places this method
+        can be used to enforce a list as return value.
+        """
+        rv = self.visit(node, *args, **kwargs)
+
+        if not isinstance(rv, list):
+            return [rv]
+
+        return rv

lib/spack/external/_vendoring/jsonschema.pyi

@@ -0,0 +1 @@
+from jsonschema import *

lib/spack/external/_vendoring/jsonschema/COPYING

@@ -0,0 +1,19 @@
+Copyright (c) 2013 Julian Berman
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

lib/spack/external/_vendoring/jsonschema/__init__.py

@@ -0,0 +1,31 @@
+"""
+An implementation of JSON Schema for Python
+
+The main functionality is provided by the validator classes for each of the
+supported JSON Schema versions.
+
+Most commonly, `validate` is the quickest way to simply validate a given
+instance under a schema, and will create a validator for you.
+"""
+
+from jsonschema.exceptions import (
+    ErrorTree, FormatError, RefResolutionError, SchemaError, ValidationError
+)
+from jsonschema._format import (
+    FormatChecker,
+    draft3_format_checker,
+    draft4_format_checker,
+    draft6_format_checker,
+    draft7_format_checker,
+)
+from jsonschema._types import TypeChecker
+from jsonschema.validators import (
+    Draft3Validator,
+    Draft4Validator,
+    Draft6Validator,
+    Draft7Validator,
+    RefResolver,
+    validate,
+)
+
+__version__ = "3.2.0"

lib/spack/external/_vendoring/jsonschema/__main__.py

@@ -0,0 +1,2 @@
+from jsonschema.cli import main
+main()

lib/spack/external/_vendoring/jsonschema/_format.py

@@ -0,0 +1,425 @@
+import datetime
+import re
+import socket
+import struct
+
+from jsonschema.compat import str_types
+from jsonschema.exceptions import FormatError
+
+
+class FormatChecker(object):
+    """
+    A ``format`` property checker.
+
+    JSON Schema does not mandate that the ``format`` property actually do any
+    validation. If validation is desired however, instances of this class can
+    be hooked into validators to enable format validation.
+
+    `FormatChecker` objects always return ``True`` when asked about
+    formats that they do not know how to validate.
+
+    To check a custom format using a function that takes an instance and
+    returns a ``bool``, use the `FormatChecker.checks` or
+    `FormatChecker.cls_checks` decorators.
+
+    Arguments:
+
+        formats (~collections.Iterable):
+
+            The known formats to validate. This argument can be used to
+            limit which formats will be used during validation.
+    """
+
+    checkers = {}
+
+    def __init__(self, formats=None):
+        if formats is None:
+            self.checkers = self.checkers.copy()
+        else:
+            self.checkers = dict((k, self.checkers[k]) for k in formats)
+
+    def __repr__(self):
+        return "<FormatChecker checkers={}>".format(sorted(self.checkers))
+
+    def checks(self, format, raises=()):
+        """
+        Register a decorated function as validating a new format.
+
+        Arguments:
+
+            format (str):
+
+                The format that the decorated function will check.
+
+            raises (Exception):
+
+                The exception(s) raised by the decorated function when an
+                invalid instance is found.
+
+                The exception object will be accessible as the
+                `jsonschema.exceptions.ValidationError.cause` attribute of the
+                resulting validation error.
+        """
+
+        def _checks(func):
+            self.checkers[format] = (func, raises)
+            return func
+        return _checks
+
+    cls_checks = classmethod(checks)
+
+    def check(self, instance, format):
+        """
+        Check whether the instance conforms to the given format.
+
+        Arguments:
+
+            instance (*any primitive type*, i.e. str, number, bool):
+
+                The instance to check
+
+            format (str):
+
+                The format that instance should conform to
+
+
+        Raises:
+
+            FormatError: if the instance does not conform to ``format``
+        """
+
+        if format not in self.checkers:
+            return
+
+        func, raises = self.checkers[format]
+        result, cause = None, None
+        try:
+            result = func(instance)
+        except raises as e:
+            cause = e
+        if not result:
+            raise FormatError(
+                "%r is not a %r" % (instance, format), cause=cause,
+            )
+
+    def conforms(self, instance, format):
+        """
+        Check whether the instance conforms to the given format.
+
+        Arguments:
+
+            instance (*any primitive type*, i.e. str, number, bool):
+
+                The instance to check
+
+            format (str):
+
+                The format that instance should conform to
+
+        Returns:
+
+            bool: whether it conformed
+        """
+
+        try:
+            self.check(instance, format)
+        except FormatError:
+            return False
+        else:
+            return True
+
+
+draft3_format_checker = FormatChecker()
+draft4_format_checker = FormatChecker()
+draft6_format_checker = FormatChecker()
+draft7_format_checker = FormatChecker()
+
+
+_draft_checkers = dict(
+    draft3=draft3_format_checker,
+    draft4=draft4_format_checker,
+    draft6=draft6_format_checker,
+    draft7=draft7_format_checker,
+)
+
+
+def _checks_drafts(
+    name=None,
+    draft3=None,
+    draft4=None,
+    draft6=None,
+    draft7=None,
+    raises=(),
+):
+    draft3 = draft3 or name
+    draft4 = draft4 or name
+    draft6 = draft6 or name
+    draft7 = draft7 or name
+
+    def wrap(func):
+        if draft3:
+            func = _draft_checkers["draft3"].checks(draft3, raises)(func)
+        if draft4:
+            func = _draft_checkers["draft4"].checks(draft4, raises)(func)
+        if draft6:
+            func = _draft_checkers["draft6"].checks(draft6, raises)(func)
+        if draft7:
+            func = _draft_checkers["draft7"].checks(draft7, raises)(func)
+
+        # Oy. This is bad global state, but relied upon for now, until
+        # deprecation. See https://github.com/Julian/jsonschema/issues/519
+        # and test_format_checkers_come_with_defaults
+        FormatChecker.cls_checks(draft7 or draft6 or draft4 or draft3, raises)(
+            func,
+        )
+        return func
+    return wrap
+
+
+@_checks_drafts(name="idn-email")
+@_checks_drafts(name="email")
+def is_email(instance):
+    if not isinstance(instance, str_types):
+        return True
+    return "@" in instance
+
+
+_ipv4_re = re.compile(r"^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$")
+
+
+@_checks_drafts(
+    draft3="ip-address", draft4="ipv4", draft6="ipv4", draft7="ipv4",
+)
+def is_ipv4(instance):
+    if not isinstance(instance, str_types):
+        return True
+    if not _ipv4_re.match(instance):
+        return False
+    return all(0 <= int(component) <= 255 for component in instance.split("."))
+
+
+if hasattr(socket, "inet_pton"):
+    # FIXME: Really this only should raise struct.error, but see the sadness
+    #        that is https://twistedmatrix.com/trac/ticket/9409
+    @_checks_drafts(
+        name="ipv6", raises=(socket.error, struct.error, ValueError),
+    )
+    def is_ipv6(instance):
+        if not isinstance(instance, str_types):
+            return True
+        return socket.inet_pton(socket.AF_INET6, instance)
+
+
+_host_name_re = re.compile(r"^[A-Za-z0-9][A-Za-z0-9\.\-]{1,255}$")
+
+
+@_checks_drafts(
+    draft3="host-name",
+    draft4="hostname",
+    draft6="hostname",
+    draft7="hostname",
+)
+def is_host_name(instance):
+    if not isinstance(instance, str_types):
+        return True
+    if not _host_name_re.match(instance):
+        return False
+    components = instance.split(".")
+    for component in components:
+        if len(component) > 63:
+            return False
+    return True
+
+
+try:
+    # The built-in `idna` codec only implements RFC 3890, so we go elsewhere.
+    import idna
+except ImportError:
+    pass
+else:
+    @_checks_drafts(draft7="idn-hostname", raises=idna.IDNAError)
+    def is_idn_host_name(instance):
+        if not isinstance(instance, str_types):
+            return True
+        idna.encode(instance)
+        return True
+
+
+try:
+    import rfc3987
+except ImportError:
+    try:
+        from rfc3986_validator import validate_rfc3986
+    except ImportError:
+        pass
+    else:
+        @_checks_drafts(name="uri")
+        def is_uri(instance):
+            if not isinstance(instance, str_types):
+                return True
+            return validate_rfc3986(instance, rule="URI")
+
+        @_checks_drafts(
+            draft6="uri-reference",
+            draft7="uri-reference",
+            raises=ValueError,
+        )
+        def is_uri_reference(instance):
+            if not isinstance(instance, str_types):
+                return True
+            return validate_rfc3986(instance, rule="URI_reference")
+
+else:
+    @_checks_drafts(draft7="iri", raises=ValueError)
+    def is_iri(instance):
+        if not isinstance(instance, str_types):
+            return True
+        return rfc3987.parse(instance, rule="IRI")
+
+    @_checks_drafts(draft7="iri-reference", raises=ValueError)
+    def is_iri_reference(instance):
+        if not isinstance(instance, str_types):
+            return True
+        return rfc3987.parse(instance, rule="IRI_reference")
+
+    @_checks_drafts(name="uri", raises=ValueError)
+    def is_uri(instance):
+        if not isinstance(instance, str_types):
+            return True
+        return rfc3987.parse(instance, rule="URI")
+
+    @_checks_drafts(
+        draft6="uri-reference",
+        draft7="uri-reference",
+        raises=ValueError,
+    )
+    def is_uri_reference(instance):
+        if not isinstance(instance, str_types):
+            return True
+        return rfc3987.parse(instance, rule="URI_reference")
+
+
+try:
+    from strict_rfc3339 import validate_rfc3339
+except ImportError:
+    try:
+        from rfc3339_validator import validate_rfc3339
+    except ImportError:
+        validate_rfc3339 = None
+
+if validate_rfc3339:
+    @_checks_drafts(name="date-time")
+    def is_datetime(instance):
+        if not isinstance(instance, str_types):
+            return True
+        return validate_rfc3339(instance)
+
+    @_checks_drafts(draft7="time")
+    def is_time(instance):
+        if not isinstance(instance, str_types):
+            return True
+        return is_datetime("1970-01-01T" + instance)
+
+
+@_checks_drafts(name="regex", raises=re.error)
+def is_regex(instance):
+    if not isinstance(instance, str_types):
+        return True
+    return re.compile(instance)
+
+
+@_checks_drafts(draft3="date", draft7="date", raises=ValueError)
+def is_date(instance):
+    if not isinstance(instance, str_types):
+        return True
+    return datetime.datetime.strptime(instance, "%Y-%m-%d")
+
+
+@_checks_drafts(draft3="time", raises=ValueError)
+def is_draft3_time(instance):
+    if not isinstance(instance, str_types):
+        return True
+    return datetime.datetime.strptime(instance, "%H:%M:%S")
+
+
+try:
+    import webcolors
+except ImportError:
+    pass
+else:
+    def is_css_color_code(instance):
+        return webcolors.normalize_hex(instance)
+
+    @_checks_drafts(draft3="color", raises=(ValueError, TypeError))
+    def is_css21_color(instance):
+        if (
+            not isinstance(instance, str_types) or
+            instance.lower() in webcolors.css21_names_to_hex
+        ):
+            return True
+        return is_css_color_code(instance)
+
+    def is_css3_color(instance):
+        if instance.lower() in webcolors.css3_names_to_hex:
+            return True
+        return is_css_color_code(instance)
+
+
+try:
+    import jsonpointer
+except ImportError:
+    pass
+else:
+    @_checks_drafts(
+        draft6="json-pointer",
+        draft7="json-pointer",
+        raises=jsonpointer.JsonPointerException,
+    )
+    def is_json_pointer(instance):
+        if not isinstance(instance, str_types):
+            return True
+        return jsonpointer.JsonPointer(instance)
+
+    # TODO: I don't want to maintain this, so it
+    #       needs to go either into jsonpointer (pending
+    #       https://github.com/stefankoegl/python-json-pointer/issues/34) or
+    #       into a new external library.
+    @_checks_drafts(
+        draft7="relative-json-pointer",
+        raises=jsonpointer.JsonPointerException,
+    )
+    def is_relative_json_pointer(instance):
+        # Definition taken from:
+        # https://tools.ietf.org/html/draft-handrews-relative-json-pointer-01#section-3
+        if not isinstance(instance, str_types):
+            return True
+        non_negative_integer, rest = [], ""
+        for i, character in enumerate(instance):
+            if character.isdigit():
+                non_negative_integer.append(character)
+                continue
+
+            if not non_negative_integer:
+                return False
+
+            rest = instance[i:]
+            break
+        return (rest == "#") or jsonpointer.JsonPointer(rest)
+
+
+try:
+    import uritemplate.exceptions
+except ImportError:
+    pass
+else:
+    @_checks_drafts(
+        draft6="uri-template",
+        draft7="uri-template",
+        raises=uritemplate.exceptions.InvalidTemplate,
+    )
+    def is_uri_template(
+        instance,
+        template_validator=uritemplate.Validator().force_balanced_braces(),
+    ):
+        template = uritemplate.URITemplate(instance)
+        return template_validator.validate(template)

lib/spack/external/_vendoring/jsonschema/_legacy_validators.py

@@ -0,0 +1,141 @@
+from jsonschema import _utils
+from jsonschema.compat import iteritems
+from jsonschema.exceptions import ValidationError
+
+
+def dependencies_draft3(validator, dependencies, instance, schema):
+    if not validator.is_type(instance, "object"):
+        return
+
+    for property, dependency in iteritems(dependencies):
+        if property not in instance:
+            continue
+
+        if validator.is_type(dependency, "object"):
+            for error in validator.descend(
+                instance, dependency, schema_path=property,
+            ):
+                yield error
+        elif validator.is_type(dependency, "string"):
+            if dependency not in instance:
+                yield ValidationError(
+                    "%r is a dependency of %r" % (dependency, property)
+                )
+        else:
+            for each in dependency:
+                if each not in instance:
+                    message = "%r is a dependency of %r"
+                    yield ValidationError(message % (each, property))
+
+
+def disallow_draft3(validator, disallow, instance, schema):
+    for disallowed in _utils.ensure_list(disallow):
+        if validator.is_valid(instance, {"type": [disallowed]}):
+            yield ValidationError(
+                "%r is disallowed for %r" % (disallowed, instance)
+            )
+
+
+def extends_draft3(validator, extends, instance, schema):
+    if validator.is_type(extends, "object"):
+        for error in validator.descend(instance, extends):
+            yield error
+        return
+    for index, subschema in enumerate(extends):
+        for error in validator.descend(instance, subschema, schema_path=index):
+            yield error
+
+
+def items_draft3_draft4(validator, items, instance, schema):
+    if not validator.is_type(instance, "array"):
+        return
+
+    if validator.is_type(items, "object"):
+        for index, item in enumerate(instance):
+            for error in validator.descend(item, items, path=index):
+                yield error
+    else:
+        for (index, item), subschema in zip(enumerate(instance), items):
+            for error in validator.descend(
+                item, subschema, path=index, schema_path=index,
+            ):
+                yield error
+
+
+def minimum_draft3_draft4(validator, minimum, instance, schema):
+    if not validator.is_type(instance, "number"):
+        return
+
+    if schema.get("exclusiveMinimum", False):
+        failed = instance <= minimum
+        cmp = "less than or equal to"
+    else:
+        failed = instance < minimum
+        cmp = "less than"
+
+    if failed:
+        yield ValidationError(
+            "%r is %s the minimum of %r" % (instance, cmp, minimum)
+        )
+
+
+def maximum_draft3_draft4(validator, maximum, instance, schema):
+    if not validator.is_type(instance, "number"):
+        return
+
+    if schema.get("exclusiveMaximum", False):
+        failed = instance >= maximum
+        cmp = "greater than or equal to"
+    else:
+        failed = instance > maximum
+        cmp = "greater than"
+
+    if failed:
+        yield ValidationError(
+            "%r is %s the maximum of %r" % (instance, cmp, maximum)
+        )
+
+
+def properties_draft3(validator, properties, instance, schema):
+    if not validator.is_type(instance, "object"):
+        return
+
+    for property, subschema in iteritems(properties):
+        if property in instance:
+            for error in validator.descend(
+                instance[property],
+                subschema,
+                path=property,
+                schema_path=property,
+            ):
+                yield error
+        elif subschema.get("required", False):
+            error = ValidationError("%r is a required property" % property)
+            error._set(
+                validator="required",
+                validator_value=subschema["required"],
+                instance=instance,
+                schema=schema,
+            )
+            error.path.appendleft(property)
+            error.schema_path.extend([property, "required"])
+            yield error
+
+
+def type_draft3(validator, types, instance, schema):
+    types = _utils.ensure_list(types)
+
+    all_errors = []
+    for index, type in enumerate(types):
+        if validator.is_type(type, "object"):
+            errors = list(validator.descend(instance, type, schema_path=index))
+            if not errors:
+                return
+            all_errors.extend(errors)
+        else:
+            if validator.is_type(instance, type):
+                return
+    else:
+        yield ValidationError(
+            _utils.types_msg(instance, types), context=all_errors,
+        )

lib/spack/external/_vendoring/jsonschema/_reflect.py

@@ -0,0 +1,155 @@
+# -*- test-case-name: twisted.test.test_reflect -*-
+# Copyright (c) Twisted Matrix Laboratories.
+# See LICENSE for details.
+
+"""
+Standardized versions of various cool and/or strange things that you can do
+with Python's reflection capabilities.
+"""
+
+import sys
+
+from jsonschema.compat import PY3
+
+
+class _NoModuleFound(Exception):
+    """
+    No module was found because none exists.
+    """
+
+
+
+class InvalidName(ValueError):
+    """
+    The given name is not a dot-separated list of Python objects.
+    """
+
+
+
+class ModuleNotFound(InvalidName):
+    """
+    The module associated with the given name doesn't exist and it can't be
+    imported.
+    """
+
+
+
+class ObjectNotFound(InvalidName):
+    """
+    The object associated with the given name doesn't exist and it can't be
+    imported.
+    """
+
+
+
+if PY3:
+    def reraise(exception, traceback):
+        raise exception.with_traceback(traceback)
+else:
+    exec("""def reraise(exception, traceback):
+        raise exception.__class__, exception, traceback""")
+
+reraise.__doc__ = """
+Re-raise an exception, with an optional traceback, in a way that is compatible
+with both Python 2 and Python 3.
+
+Note that on Python 3, re-raised exceptions will be mutated, with their
+C{__traceback__} attribute being set.
+
+@param exception: The exception instance.
+@param traceback: The traceback to use, or C{None} indicating a new traceback.
+"""
+
+
+def _importAndCheckStack(importName):
+    """
+    Import the given name as a module, then walk the stack to determine whether
+    the failure was the module not existing, or some code in the module (for
+    example a dependent import) failing.  This can be helpful to determine
+    whether any actual application code was run.  For example, to distiguish
+    administrative error (entering the wrong module name), from programmer
+    error (writing buggy code in a module that fails to import).
+
+    @param importName: The name of the module to import.
+    @type importName: C{str}
+    @raise Exception: if something bad happens.  This can be any type of
+        exception, since nobody knows what loading some arbitrary code might
+        do.
+    @raise _NoModuleFound: if no module was found.
+    """
+    try:
+        return __import__(importName)
+    except ImportError:
+        excType, excValue, excTraceback = sys.exc_info()
+        while excTraceback:
+            execName = excTraceback.tb_frame.f_globals["__name__"]
+            # in Python 2 execName is None when an ImportError is encountered,
+            # where in Python 3 execName is equal to the importName.
+            if execName is None or execName == importName:
+                reraise(excValue, excTraceback)
+            excTraceback = excTraceback.tb_next
+        raise _NoModuleFound()
+
+
+
+def namedAny(name):
+    """
+    Retrieve a Python object by its fully qualified name from the global Python
+    module namespace.  The first part of the name, that describes a module,
+    will be discovered and imported.  Each subsequent part of the name is
+    treated as the name of an attribute of the object specified by all of the
+    name which came before it.  For example, the fully-qualified name of this
+    object is 'twisted.python.reflect.namedAny'.
+
+    @type name: L{str}
+    @param name: The name of the object to return.
+
+    @raise InvalidName: If the name is an empty string, starts or ends with
+        a '.', or is otherwise syntactically incorrect.
+
+    @raise ModuleNotFound: If the name is syntactically correct but the
+        module it specifies cannot be imported because it does not appear to
+        exist.
+
+    @raise ObjectNotFound: If the name is syntactically correct, includes at
+        least one '.', but the module it specifies cannot be imported because
+        it does not appear to exist.
+
+    @raise AttributeError: If an attribute of an object along the way cannot be
+        accessed, or a module along the way is not found.
+
+    @return: the Python object identified by 'name'.
+    """
+    if not name:
+        raise InvalidName('Empty module name')
+
+    names = name.split('.')
+
+    # if the name starts or ends with a '.' or contains '..', the __import__
+    # will raise an 'Empty module name' error. This will provide a better error
+    # message.
+    if '' in names:
+        raise InvalidName(
+            "name must be a string giving a '.'-separated list of Python "
+            "identifiers, not %r" % (name,))
+
+    topLevelPackage = None
+    moduleNames = names[:]
+    while not topLevelPackage:
+        if moduleNames:
+            trialname = '.'.join(moduleNames)
+            try:
+                topLevelPackage = _importAndCheckStack(trialname)
+            except _NoModuleFound:
+                moduleNames.pop()
+        else:
+            if len(names) == 1:
+                raise ModuleNotFound("No module named %r" % (name,))
+            else:
+                raise ObjectNotFound('%r does not name an object' % (name,))
+
+    obj = topLevelPackage
+    for n in names[1:]:
+        obj = getattr(obj, n)
+
+    return obj

lib/spack/external/_vendoring/jsonschema/_types.py

@@ -0,0 +1,188 @@
+import numbers
+
+from pyrsistent import pmap
+import attr
+
+from jsonschema.compat import int_types, str_types
+from jsonschema.exceptions import UndefinedTypeCheck
+
+
+def is_array(checker, instance):
+    return isinstance(instance, list)
+
+
+def is_bool(checker, instance):
+    return isinstance(instance, bool)
+
+
+def is_integer(checker, instance):
+    # bool inherits from int, so ensure bools aren't reported as ints
+    if isinstance(instance, bool):
+        return False
+    return isinstance(instance, int_types)
+
+
+def is_null(checker, instance):
+    return instance is None
+
+
+def is_number(checker, instance):
+    # bool inherits from int, so ensure bools aren't reported as ints
+    if isinstance(instance, bool):
+        return False
+    return isinstance(instance, numbers.Number)
+
+
+def is_object(checker, instance):
+    return isinstance(instance, dict)
+
+
+def is_string(checker, instance):
+    return isinstance(instance, str_types)
+
+
+def is_any(checker, instance):
+    return True
+
+
+@attr.s(frozen=True)
+class TypeChecker(object):
+    """
+    A ``type`` property checker.
+
+    A `TypeChecker` performs type checking for an `IValidator`. Type
+    checks to perform are updated using `TypeChecker.redefine` or
+    `TypeChecker.redefine_many` and removed via `TypeChecker.remove`.
+    Each of these return a new `TypeChecker` object.
+
+    Arguments:
+
+        type_checkers (dict):
+
+            The initial mapping of types to their checking functions.
+    """
+    _type_checkers = attr.ib(default=pmap(), converter=pmap)
+
+    def is_type(self, instance, type):
+        """
+        Check if the instance is of the appropriate type.
+
+        Arguments:
+
+            instance (object):
+
+                The instance to check
+
+            type (str):
+
+                The name of the type that is expected.
+
+        Returns:
+
+            bool: Whether it conformed.
+
+
+        Raises:
+
+            `jsonschema.exceptions.UndefinedTypeCheck`:
+                if type is unknown to this object.
+        """
+        try:
+            fn = self._type_checkers[type]
+        except KeyError:
+            raise UndefinedTypeCheck(type)
+
+        return fn(self, instance)
+
+    def redefine(self, type, fn):
+        """
+        Produce a new checker with the given type redefined.
+
+        Arguments:
+
+            type (str):
+
+                The name of the type to check.
+
+            fn (collections.Callable):
+
+                A function taking exactly two parameters - the type
+                checker calling the function and the instance to check.
+                The function should return true if instance is of this
+                type and false otherwise.
+
+        Returns:
+
+            A new `TypeChecker` instance.
+        """
+        return self.redefine_many({type: fn})
+
+    def redefine_many(self, definitions=()):
+        """
+        Produce a new checker with the given types redefined.
+
+        Arguments:
+
+            definitions (dict):
+
+                A dictionary mapping types to their checking functions.
+
+        Returns:
+
+            A new `TypeChecker` instance.
+        """
+        return attr.evolve(
+            self, type_checkers=self._type_checkers.update(definitions),
+        )
+
+    def remove(self, *types):
+        """
+        Produce a new checker with the given types forgotten.
+
+        Arguments:
+
+            types (~collections.Iterable):
+
+                the names of the types to remove.
+
+        Returns:
+
+            A new `TypeChecker` instance
+
+        Raises:
+
+            `jsonschema.exceptions.UndefinedTypeCheck`:
+
+                if any given type is unknown to this object
+        """
+
+        checkers = self._type_checkers
+        for each in types:
+            try:
+                checkers = checkers.remove(each)
+            except KeyError:
+                raise UndefinedTypeCheck(each)
+        return attr.evolve(self, type_checkers=checkers)
+
+
+draft3_type_checker = TypeChecker(
+    {
+        u"any": is_any,
+        u"array": is_array,
+        u"boolean": is_bool,
+        u"integer": is_integer,
+        u"object": is_object,
+        u"null": is_null,
+        u"number": is_number,
+        u"string": is_string,
+    },
+)
+draft4_type_checker = draft3_type_checker.remove(u"any")
+draft6_type_checker = draft4_type_checker.redefine(
+    u"integer",
+    lambda checker, instance: (
+        is_integer(checker, instance) or
+        isinstance(instance, float) and instance.is_integer()
+    ),
+)
+draft7_type_checker = draft6_type_checker

lib/spack/external/_vendoring/jsonschema/_utils.py

@@ -0,0 +1,212 @@
+import itertools
+import json
+import pkgutil
+import re
+
+from jsonschema.compat import MutableMapping, str_types, urlsplit
+
+
+class URIDict(MutableMapping):
+    """
+    Dictionary which uses normalized URIs as keys.
+    """
+
+    def normalize(self, uri):
+        return urlsplit(uri).geturl()
+
+    def __init__(self, *args, **kwargs):
+        self.store = dict()
+        self.store.update(*args, **kwargs)
+
+    def __getitem__(self, uri):
+        return self.store[self.normalize(uri)]
+
+    def __setitem__(self, uri, value):
+        self.store[self.normalize(uri)] = value
+
+    def __delitem__(self, uri):
+        del self.store[self.normalize(uri)]
+
+    def __iter__(self):
+        return iter(self.store)
+
+    def __len__(self):
+        return len(self.store)
+
+    def __repr__(self):
+        return repr(self.store)
+
+
+class Unset(object):
+    """
+    An as-of-yet unset attribute or unprovided default parameter.
+    """
+
+    def __repr__(self):
+        return "<unset>"
+
+
+def load_schema(name):
+    """
+    Load a schema from ./schemas/``name``.json and return it.
+    """
+
+    data = pkgutil.get_data("jsonschema", "schemas/{0}.json".format(name))
+    return json.loads(data.decode("utf-8"))
+
+
+def indent(string, times=1):
+    """
+    A dumb version of `textwrap.indent` from Python 3.3.
+    """
+
+    return "\n".join(" " * (4 * times) + line for line in string.splitlines())
+
+
+def format_as_index(indices):
+    """
+    Construct a single string containing indexing operations for the indices.
+
+    For example, [1, 2, "foo"] -> [1][2]["foo"]
+
+    Arguments:
+
+        indices (sequence):
+
+            The indices to format.
+    """
+
+    if not indices:
+        return ""
+    return "[%s]" % "][".join(repr(index) for index in indices)
+
+
+def find_additional_properties(instance, schema):
+    """
+    Return the set of additional properties for the given ``instance``.
+
+    Weeds out properties that should have been validated by ``properties`` and
+    / or ``patternProperties``.
+
+    Assumes ``instance`` is dict-like already.
+    """
+
+    properties = schema.get("properties", {})
+    patterns = "|".join(schema.get("patternProperties", {}))
+    for property in instance:
+        if property not in properties:
+            if patterns and re.search(patterns, property):
+                continue
+            yield property
+
+
+def extras_msg(extras):
+    """
+    Create an error message for extra items or properties.
+    """
+
+    if len(extras) == 1:
+        verb = "was"
+    else:
+        verb = "were"
+    return ", ".join(repr(extra) for extra in extras), verb
+
+
+def types_msg(instance, types):
+    """
+    Create an error message for a failure to match the given types.
+
+    If the ``instance`` is an object and contains a ``name`` property, it will
+    be considered to be a description of that object and used as its type.
+
+    Otherwise the message is simply the reprs of the given ``types``.
+    """
+
+    reprs = []
+    for type in types:
+        try:
+            reprs.append(repr(type["name"]))
+        except Exception:
+            reprs.append(repr(type))
+    return "%r is not of type %s" % (instance, ", ".join(reprs))
+
+
+def flatten(suitable_for_isinstance):
+    """
+    isinstance() can accept a bunch of really annoying different types:
+        * a single type
+        * a tuple of types
+        * an arbitrary nested tree of tuples
+
+    Return a flattened tuple of the given argument.
+    """
+
+    types = set()
+
+    if not isinstance(suitable_for_isinstance, tuple):
+        suitable_for_isinstance = (suitable_for_isinstance,)
+    for thing in suitable_for_isinstance:
+        if isinstance(thing, tuple):
+            types.update(flatten(thing))
+        else:
+            types.add(thing)
+    return tuple(types)
+
+
+def ensure_list(thing):
+    """
+    Wrap ``thing`` in a list if it's a single str.
+
+    Otherwise, return it unchanged.
+    """
+
+    if isinstance(thing, str_types):
+        return [thing]
+    return thing
+
+
+def equal(one, two):
+    """
+    Check if two things are equal, but evade booleans and ints being equal.
+    """
+    return unbool(one) == unbool(two)
+
+
+def unbool(element, true=object(), false=object()):
+    """
+    A hack to make True and 1 and False and 0 unique for ``uniq``.
+    """
+
+    if element is True:
+        return true
+    elif element is False:
+        return false
+    return element
+
+
+def uniq(container):
+    """
+    Check if all of a container's elements are unique.
+
+    Successively tries first to rely that the elements are hashable, then
+    falls back on them being sortable, and finally falls back on brute
+    force.
+    """
+
+    try:
+        return len(set(unbool(i) for i in container)) == len(container)
+    except TypeError:
+        try:
+            sort = sorted(unbool(i) for i in container)
+            sliced = itertools.islice(sort, 1, None)
+            for i, j in zip(sort, sliced):
+                if i == j:
+                    return False
+        except (NotImplementedError, TypeError):
+            seen = []
+            for e in container:
+                e = unbool(e)
+                if e in seen:
+                    return False
+                seen.append(e)
+    return True

lib/spack/external/_vendoring/jsonschema/_validators.py

@@ -0,0 +1,373 @@
+import re
+
+from jsonschema._utils import (
+    ensure_list,
+    equal,
+    extras_msg,
+    find_additional_properties,
+    types_msg,
+    unbool,
+    uniq,
+)
+from jsonschema.exceptions import FormatError, ValidationError
+from jsonschema.compat import iteritems
+
+
+def patternProperties(validator, patternProperties, instance, schema):
+    if not validator.is_type(instance, "object"):
+        return
+
+    for pattern, subschema in iteritems(patternProperties):
+        for k, v in iteritems(instance):
+            if re.search(pattern, k):
+                for error in validator.descend(
+                    v, subschema, path=k, schema_path=pattern,
+                ):
+                    yield error
+
+
+def propertyNames(validator, propertyNames, instance, schema):
+    if not validator.is_type(instance, "object"):
+        return
+
+    for property in instance:
+        for error in validator.descend(
+            instance=property,
+            schema=propertyNames,
+        ):
+            yield error
+
+
+def additionalProperties(validator, aP, instance, schema):
+    if not validator.is_type(instance, "object"):
+        return
+
+    extras = set(find_additional_properties(instance, schema))
+
+    if validator.is_type(aP, "object"):
+        for extra in extras:
+            for error in validator.descend(instance[extra], aP, path=extra):
+                yield error
+    elif not aP and extras:
+        if "patternProperties" in schema:
+            patterns = sorted(schema["patternProperties"])
+            if len(extras) == 1:
+                verb = "does"
+            else:
+                verb = "do"
+            error = "%s %s not match any of the regexes: %s" % (
+                ", ".join(map(repr, sorted(extras))),
+                verb,
+                ", ".join(map(repr, patterns)),
+            )
+            yield ValidationError(error)
+        else:
+            error = "Additional properties are not allowed (%s %s unexpected)"
+            yield ValidationError(error % extras_msg(extras))
+
+
+def items(validator, items, instance, schema):
+    if not validator.is_type(instance, "array"):
+        return
+
+    if validator.is_type(items, "array"):
+        for (index, item), subschema in zip(enumerate(instance), items):
+            for error in validator.descend(
+                item, subschema, path=index, schema_path=index,
+            ):
+                yield error
+    else:
+        for index, item in enumerate(instance):
+            for error in validator.descend(item, items, path=index):
+                yield error
+
+
+def additionalItems(validator, aI, instance, schema):
+    if (
+        not validator.is_type(instance, "array") or
+        validator.is_type(schema.get("items", {}), "object")
+    ):
+        return
+
+    len_items = len(schema.get("items", []))
+    if validator.is_type(aI, "object"):
+        for index, item in enumerate(instance[len_items:], start=len_items):
+            for error in validator.descend(item, aI, path=index):
+                yield error
+    elif not aI and len(instance) > len(schema.get("items", [])):
+        error = "Additional items are not allowed (%s %s unexpected)"
+        yield ValidationError(
+            error %
+            extras_msg(instance[len(schema.get("items", [])):])
+        )
+
+
+def const(validator, const, instance, schema):
+    if not equal(instance, const):
+        yield ValidationError("%r was expected" % (const,))
+
+
+def contains(validator, contains, instance, schema):
+    if not validator.is_type(instance, "array"):
+        return
+
+    if not any(validator.is_valid(element, contains) for element in instance):
+        yield ValidationError(
+            "None of %r are valid under the given schema" % (instance,)
+        )
+
+
+def exclusiveMinimum(validator, minimum, instance, schema):
+    if not validator.is_type(instance, "number"):
+        return
+
+    if instance <= minimum:
+        yield ValidationError(
+            "%r is less than or equal to the minimum of %r" % (
+                instance, minimum,
+            ),
+        )
+
+
+def exclusiveMaximum(validator, maximum, instance, schema):
+    if not validator.is_type(instance, "number"):
+        return
+
+    if instance >= maximum:
+        yield ValidationError(
+            "%r is greater than or equal to the maximum of %r" % (
+                instance, maximum,
+            ),
+        )
+
+
+def minimum(validator, minimum, instance, schema):
+    if not validator.is_type(instance, "number"):
+        return
+
+    if instance < minimum:
+        yield ValidationError(
+            "%r is less than the minimum of %r" % (instance, minimum)
+        )
+
+
+def maximum(validator, maximum, instance, schema):
+    if not validator.is_type(instance, "number"):
+        return
+
+    if instance > maximum:
+        yield ValidationError(
+            "%r is greater than the maximum of %r" % (instance, maximum)
+        )
+
+
+def multipleOf(validator, dB, instance, schema):
+    if not validator.is_type(instance, "number"):
+        return
+
+    if isinstance(dB, float):
+        quotient = instance / dB
+        failed = int(quotient) != quotient
+    else:
+        failed = instance % dB
+
+    if failed:
+        yield ValidationError("%r is not a multiple of %r" % (instance, dB))
+
+
+def minItems(validator, mI, instance, schema):
+    if validator.is_type(instance, "array") and len(instance) < mI:
+        yield ValidationError("%r is too short" % (instance,))
+
+
+def maxItems(validator, mI, instance, schema):
+    if validator.is_type(instance, "array") and len(instance) > mI:
+        yield ValidationError("%r is too long" % (instance,))
+
+
+def uniqueItems(validator, uI, instance, schema):
+    if (
+        uI and
+        validator.is_type(instance, "array") and
+        not uniq(instance)
+    ):
+        yield ValidationError("%r has non-unique elements" % (instance,))
+
+
+def pattern(validator, patrn, instance, schema):
+    if (
+        validator.is_type(instance, "string") and
+        not re.search(patrn, instance)
+    ):
+        yield ValidationError("%r does not match %r" % (instance, patrn))
+
+
+def format(validator, format, instance, schema):
+    if validator.format_checker is not None:
+        try:
+            validator.format_checker.check(instance, format)
+        except FormatError as error:
+            yield ValidationError(error.message, cause=error.cause)
+
+
+def minLength(validator, mL, instance, schema):
+    if validator.is_type(instance, "string") and len(instance) < mL:
+        yield ValidationError("%r is too short" % (instance,))
+
+
+def maxLength(validator, mL, instance, schema):
+    if validator.is_type(instance, "string") and len(instance) > mL:
+        yield ValidationError("%r is too long" % (instance,))
+
+
+def dependencies(validator, dependencies, instance, schema):
+    if not validator.is_type(instance, "object"):
+        return
+
+    for property, dependency in iteritems(dependencies):
+        if property not in instance:
+            continue
+
+        if validator.is_type(dependency, "array"):
+            for each in dependency:
+                if each not in instance:
+                    message = "%r is a dependency of %r"
+                    yield ValidationError(message % (each, property))
+        else:
+            for error in validator.descend(
+                instance, dependency, schema_path=property,
+            ):
+                yield error
+
+
+def enum(validator, enums, instance, schema):
+    if instance == 0 or instance == 1:
+        unbooled = unbool(instance)
+        if all(unbooled != unbool(each) for each in enums):
+            yield ValidationError("%r is not one of %r" % (instance, enums))
+    elif instance not in enums:
+        yield ValidationError("%r is not one of %r" % (instance, enums))
+
+
+def ref(validator, ref, instance, schema):
+    resolve = getattr(validator.resolver, "resolve", None)
+    if resolve is None:
+        with validator.resolver.resolving(ref) as resolved:
+            for error in validator.descend(instance, resolved):
+                yield error
+    else:
+        scope, resolved = validator.resolver.resolve(ref)
+        validator.resolver.push_scope(scope)
+
+        try:
+            for error in validator.descend(instance, resolved):
+                yield error
+        finally:
+            validator.resolver.pop_scope()
+
+
+def type(validator, types, instance, schema):
+    types = ensure_list(types)
+
+    if not any(validator.is_type(instance, type) for type in types):
+        yield ValidationError(types_msg(instance, types))
+
+
+def properties(validator, properties, instance, schema):
+    if not validator.is_type(instance, "object"):
+        return
+
+    for property, subschema in iteritems(properties):
+        if property in instance:
+            for error in validator.descend(
+                instance[property],
+                subschema,
+                path=property,
+                schema_path=property,
+            ):
+                yield error
+
+
+def required(validator, required, instance, schema):
+    if not validator.is_type(instance, "object"):
+        return
+    for property in required:
+        if property not in instance:
+            yield ValidationError("%r is a required property" % property)
+
+
+def minProperties(validator, mP, instance, schema):
+    if validator.is_type(instance, "object") and len(instance) < mP:
+        yield ValidationError(
+            "%r does not have enough properties" % (instance,)
+        )
+
+
+def maxProperties(validator, mP, instance, schema):
+    if not validator.is_type(instance, "object"):
+        return
+    if validator.is_type(instance, "object") and len(instance) > mP:
+        yield ValidationError("%r has too many properties" % (instance,))
+
+
+def allOf(validator, allOf, instance, schema):
+    for index, subschema in enumerate(allOf):
+        for error in validator.descend(instance, subschema, schema_path=index):
+            yield error
+
+
+def anyOf(validator, anyOf, instance, schema):
+    all_errors = []
+    for index, subschema in enumerate(anyOf):
+        errs = list(validator.descend(instance, subschema, schema_path=index))
+        if not errs:
+            break
+        all_errors.extend(errs)
+    else:
+        yield ValidationError(
+            "%r is not valid under any of the given schemas" % (instance,),
+            context=all_errors,
+        )
+
+
+def oneOf(validator, oneOf, instance, schema):
+    subschemas = enumerate(oneOf)
+    all_errors = []
+    for index, subschema in subschemas:
+        errs = list(validator.descend(instance, subschema, schema_path=index))
+        if not errs:
+            first_valid = subschema
+            break
+        all_errors.extend(errs)
+    else:
+        yield ValidationError(
+            "%r is not valid under any of the given schemas" % (instance,),
+            context=all_errors,
+        )
+
+    more_valid = [s for i, s in subschemas if validator.is_valid(instance, s)]
+    if more_valid:
+        more_valid.append(first_valid)
+        reprs = ", ".join(repr(schema) for schema in more_valid)
+        yield ValidationError(
+            "%r is valid under each of %s" % (instance, reprs)
+        )
+
+
+def not_(validator, not_schema, instance, schema):
+    if validator.is_valid(instance, not_schema):
+        yield ValidationError(
+            "%r is not allowed for %r" % (not_schema, instance)
+        )
+
+
+def if_(validator, if_schema, instance, schema):
+    if validator.is_valid(instance, if_schema):
+        if u"then" in schema:
+            then = schema[u"then"]
+            for error in validator.descend(instance, then, schema_path="then"):
+                yield error
+    elif u"else" in schema:
+        else_ = schema[u"else"]
+        for error in validator.descend(instance, else_, schema_path="else"):
+            yield error

lib/spack/external/_vendoring/jsonschema/benchmarks/__init__.py

@@ -0,0 +1,5 @@
+"""
+Benchmarks for validation.
+
+This package is *not* public API.
+"""

lib/spack/external/_vendoring/jsonschema/benchmarks/issue232.py

@@ -0,0 +1,26 @@
+#!/usr/bin/env python
+"""
+A performance benchmark using the example from issue #232.
+
+See https://github.com/Julian/jsonschema/pull/232.
+"""
+from twisted.python.filepath import FilePath
+from pyperf import Runner
+from pyrsistent import m
+
+from jsonschema.tests._suite import Version
+import jsonschema
+
+
+issue232 = Version(
+    path=FilePath(__file__).sibling("issue232"),
+    remotes=m(),
+    name="issue232",
+)
+
+
+if __name__ == "__main__":
+    issue232.benchmark(
+        runner=Runner(),
+        Validator=jsonschema.Draft4Validator,
+    )

lib/spack/external/_vendoring/jsonschema/benchmarks/json_schema_test_suite.py

@@ -0,0 +1,14 @@
+#!/usr/bin/env python
+"""
+A performance benchmark using the official test suite.
+
+This benchmarks jsonschema using every valid example in the
+JSON-Schema-Test-Suite. It will take some time to complete.
+"""
+from pyperf import Runner
+
+from jsonschema.tests._suite import Suite
+
+
+if __name__ == "__main__":
+    Suite().benchmark(runner=Runner())

lib/spack/external/_vendoring/jsonschema/cli.py

@@ -0,0 +1,90 @@
+"""
+The ``jsonschema`` command line.
+"""
+from __future__ import absolute_import
+import argparse
+import json
+import sys
+
+from jsonschema import __version__
+from jsonschema._reflect import namedAny
+from jsonschema.validators import validator_for
+
+
+def _namedAnyWithDefault(name):
+    if "." not in name:
+        name = "jsonschema." + name
+    return namedAny(name)
+
+
+def _json_file(path):
+    with open(path) as file:
+        return json.load(file)
+
+
+parser = argparse.ArgumentParser(
+    description="JSON Schema Validation CLI",
+)
+parser.add_argument(
+    "-i", "--instance",
+    action="append",
+    dest="instances",
+    type=_json_file,
+    help=(
+        "a path to a JSON instance (i.e. filename.json) "
+        "to validate (may be specified multiple times)"
+    ),
+)
+parser.add_argument(
+    "-F", "--error-format",
+    default="{error.instance}: {error.message}\n",
+    help=(
+        "the format to use for each error output message, specified in "
+        "a form suitable for passing to str.format, which will be called "
+        "with 'error' for each error"
+    ),
+)
+parser.add_argument(
+    "-V", "--validator",
+    type=_namedAnyWithDefault,
+    help=(
+        "the fully qualified object name of a validator to use, or, for "
+        "validators that are registered with jsonschema, simply the name "
+        "of the class."
+    ),
+)
+parser.add_argument(
+    "--version",
+    action="version",
+    version=__version__,
+)
+parser.add_argument(
+    "schema",
+    help="the JSON Schema to validate with (i.e. schema.json)",
+    type=_json_file,
+)
+
+
+def parse_args(args):
+    arguments = vars(parser.parse_args(args=args or ["--help"]))
+    if arguments["validator"] is None:
+        arguments["validator"] = validator_for(arguments["schema"])
+    return arguments
+
+
+def main(args=sys.argv[1:]):
+    sys.exit(run(arguments=parse_args(args=args)))
+
+
+def run(arguments, stdout=sys.stdout, stderr=sys.stderr):
+    error_format = arguments["error_format"]
+    validator = arguments["validator"](schema=arguments["schema"])
+
+    validator.check_schema(arguments["schema"])
+
+    errored = False
+    for instance in arguments["instances"] or ():
+        for error in validator.iter_errors(instance):
+            stderr.write(error_format.format(error=error))
+            errored = True
+    return errored

lib/spack/external/_vendoring/jsonschema/compat.py

@@ -0,0 +1,55 @@
+"""
+Python 2/3 compatibility helpers.
+
+Note: This module is *not* public API.
+"""
+import contextlib
+import operator
+import sys
+
+
+try:
+    from collections.abc import MutableMapping, Sequence  # noqa
+except ImportError:
+    from collections import MutableMapping, Sequence  # noqa
+
+PY3 = sys.version_info[0] >= 3
+
+if PY3:
+    zip = zip
+    from functools import lru_cache
+    from io import StringIO as NativeIO
+    from urllib.parse import (
+        unquote, urljoin, urlunsplit, SplitResult, urlsplit
+    )
+    from urllib.request import pathname2url, urlopen
+    str_types = str,
+    int_types = int,
+    iteritems = operator.methodcaller("items")
+else:
+    from itertools import izip as zip  # noqa
+    from io import BytesIO as NativeIO
+    from urlparse import urljoin, urlunsplit, SplitResult, urlsplit
+    from urllib import pathname2url, unquote  # noqa
+    import urllib2  # noqa
+    def urlopen(*args, **kwargs):
+        return contextlib.closing(urllib2.urlopen(*args, **kwargs))
+
+    str_types = basestring
+    int_types = int, long
+    iteritems = operator.methodcaller("iteritems")
+
+    from functools32 import lru_cache
+
+
+def urldefrag(url):
+    if "#" in url:
+        s, n, p, q, frag = urlsplit(url)
+        defrag = urlunsplit((s, n, p, q, ""))
+    else:
+        defrag = url
+        frag = ""
+    return defrag, frag
+
+
+# flake8: noqa

lib/spack/external/_vendoring/jsonschema/exceptions.py

@@ -0,0 +1,374 @@
+"""
+Validation errors, and some surrounding helpers.
+"""
+from collections import defaultdict, deque
+import itertools
+import pprint
+import textwrap
+
+import attr
+
+from jsonschema import _utils
+from jsonschema.compat import PY3, iteritems
+
+
+WEAK_MATCHES = frozenset(["anyOf", "oneOf"])
+STRONG_MATCHES = frozenset()
+
+_unset = _utils.Unset()
+
+
+class _Error(Exception):
+    def __init__(
+        self,
+        message,
+        validator=_unset,
+        path=(),
+        cause=None,
+        context=(),
+        validator_value=_unset,
+        instance=_unset,
+        schema=_unset,
+        schema_path=(),
+        parent=None,
+    ):
+        super(_Error, self).__init__(
+            message,
+            validator,
+            path,
+            cause,
+            context,
+            validator_value,
+            instance,
+            schema,
+            schema_path,
+            parent,
+        )
+        self.message = message
+        self.path = self.relative_path = deque(path)
+        self.schema_path = self.relative_schema_path = deque(schema_path)
+        self.context = list(context)
+        self.cause = self.__cause__ = cause
+        self.validator = validator
+        self.validator_value = validator_value
+        self.instance = instance
+        self.schema = schema
+        self.parent = parent
+
+        for error in context:
+            error.parent = self
+
+    def __repr__(self):
+        return "<%s: %r>" % (self.__class__.__name__, self.message)
+
+    def __unicode__(self):
+        essential_for_verbose = (
+            self.validator, self.validator_value, self.instance, self.schema,
+        )
+        if any(m is _unset for m in essential_for_verbose):
+            return self.message
+
+        pschema = pprint.pformat(self.schema, width=72)
+        pinstance = pprint.pformat(self.instance, width=72)
+        return self.message + textwrap.dedent("""
+
+            Failed validating %r in %s%s:
+            %s
+
+            On %s%s:
+            %s
+            """.rstrip()
+        ) % (
+            self.validator,
+            self._word_for_schema_in_error_message,
+            _utils.format_as_index(list(self.relative_schema_path)[:-1]),
+            _utils.indent(pschema),
+            self._word_for_instance_in_error_message,
+            _utils.format_as_index(self.relative_path),
+            _utils.indent(pinstance),
+        )
+
+    if PY3:
+        __str__ = __unicode__
+    else:
+        def __str__(self):
+            return unicode(self).encode("utf-8")
+
+    @classmethod
+    def create_from(cls, other):
+        return cls(**other._contents())
+
+    @property
+    def absolute_path(self):
+        parent = self.parent
+        if parent is None:
+            return self.relative_path
+
+        path = deque(self.relative_path)
+        path.extendleft(reversed(parent.absolute_path))
+        return path
+
+    @property
+    def absolute_schema_path(self):
+        parent = self.parent
+        if parent is None:
+            return self.relative_schema_path
+
+        path = deque(self.relative_schema_path)
+        path.extendleft(reversed(parent.absolute_schema_path))
+        return path
+
+    def _set(self, **kwargs):
+        for k, v in iteritems(kwargs):
+            if getattr(self, k) is _unset:
+                setattr(self, k, v)
+
+    def _contents(self):
+        attrs = (
+            "message", "cause", "context", "validator", "validator_value",
+            "path", "schema_path", "instance", "schema", "parent",
+        )
+        return dict((attr, getattr(self, attr)) for attr in attrs)
+
+
+class ValidationError(_Error):
+    """
+    An instance was invalid under a provided schema.
+    """
+
+    _word_for_schema_in_error_message = "schema"
+    _word_for_instance_in_error_message = "instance"
+
+
+class SchemaError(_Error):
+    """
+    A schema was invalid under its corresponding metaschema.
+    """
+
+    _word_for_schema_in_error_message = "metaschema"
+    _word_for_instance_in_error_message = "schema"
+
+
+@attr.s(hash=True)
+class RefResolutionError(Exception):
+    """
+    A ref could not be resolved.
+    """
+
+    _cause = attr.ib()
+
+    def __str__(self):
+        return str(self._cause)
+
+
+class UndefinedTypeCheck(Exception):
+    """
+    A type checker was asked to check a type it did not have registered.
+    """
+
+    def __init__(self, type):
+        self.type = type
+
+    def __unicode__(self):
+        return "Type %r is unknown to this type checker" % self.type
+
+    if PY3:
+        __str__ = __unicode__
+    else:
+        def __str__(self):
+            return unicode(self).encode("utf-8")
+
+
+class UnknownType(Exception):
+    """
+    A validator was asked to validate an instance against an unknown type.
+    """
+
+    def __init__(self, type, instance, schema):
+        self.type = type
+        self.instance = instance
+        self.schema = schema
+
+    def __unicode__(self):
+        pschema = pprint.pformat(self.schema, width=72)
+        pinstance = pprint.pformat(self.instance, width=72)
+        return textwrap.dedent("""
+            Unknown type %r for validator with schema:
+            %s
+
+            While checking instance:
+            %s
+            """.rstrip()
+        ) % (self.type, _utils.indent(pschema), _utils.indent(pinstance))
+
+    if PY3:
+        __str__ = __unicode__
+    else:
+        def __str__(self):
+            return unicode(self).encode("utf-8")
+
+
+class FormatError(Exception):
+    """
+    Validating a format failed.
+    """
+
+    def __init__(self, message, cause=None):
+        super(FormatError, self).__init__(message, cause)
+        self.message = message
+        self.cause = self.__cause__ = cause
+
+    def __unicode__(self):
+        return self.message
+
+    if PY3:
+        __str__ = __unicode__
+    else:
+        def __str__(self):
+            return self.message.encode("utf-8")
+
+
+class ErrorTree(object):
+    """
+    ErrorTrees make it easier to check which validations failed.
+    """
+
+    _instance = _unset
+
+    def __init__(self, errors=()):
+        self.errors = {}
+        self._contents = defaultdict(self.__class__)
+
+        for error in errors:
+            container = self
+            for element in error.path:
+                container = container[element]
+            container.errors[error.validator] = error
+
+            container._instance = error.instance
+
+    def __contains__(self, index):
+        """
+        Check whether ``instance[index]`` has any errors.
+        """
+
+        return index in self._contents
+
+    def __getitem__(self, index):
+        """
+        Retrieve the child tree one level down at the given ``index``.
+
+        If the index is not in the instance that this tree corresponds to and
+        is not known by this tree, whatever error would be raised by
+        ``instance.__getitem__`` will be propagated (usually this is some
+        subclass of `exceptions.LookupError`.
+        """
+
+        if self._instance is not _unset and index not in self:
+            self._instance[index]
+        return self._contents[index]
+
+    def __setitem__(self, index, value):
+        """
+        Add an error to the tree at the given ``index``.
+        """
+        self._contents[index] = value
+
+    def __iter__(self):
+        """
+        Iterate (non-recursively) over the indices in the instance with errors.
+        """
+
+        return iter(self._contents)
+
+    def __len__(self):
+        """
+        Return the `total_errors`.
+        """
+        return self.total_errors
+
+    def __repr__(self):
+        return "<%s (%s total errors)>" % (self.__class__.__name__, len(self))
+
+    @property
+    def total_errors(self):
+        """
+        The total number of errors in the entire tree, including children.
+        """
+
+        child_errors = sum(len(tree) for _, tree in iteritems(self._contents))
+        return len(self.errors) + child_errors
+
+
+def by_relevance(weak=WEAK_MATCHES, strong=STRONG_MATCHES):
+    """
+    Create a key function that can be used to sort errors by relevance.
+
+    Arguments:
+        weak (set):
+            a collection of validator names to consider to be "weak".
+            If there are two errors at the same level of the instance
+            and one is in the set of weak validator names, the other
+            error will take priority. By default, :validator:`anyOf` and
+            :validator:`oneOf` are considered weak validators and will
+            be superseded by other same-level validation errors.
+
+        strong (set):
+            a collection of validator names to consider to be "strong"
+    """
+    def relevance(error):
+        validator = error.validator
+        return -len(error.path), validator not in weak, validator in strong
+    return relevance
+
+
+relevance = by_relevance()
+
+
+def best_match(errors, key=relevance):
+    """
+    Try to find an error that appears to be the best match among given errors.
+
+    In general, errors that are higher up in the instance (i.e. for which
+    `ValidationError.path` is shorter) are considered better matches,
+    since they indicate "more" is wrong with the instance.
+
+    If the resulting match is either :validator:`oneOf` or :validator:`anyOf`,
+    the *opposite* assumption is made -- i.e. the deepest error is picked,
+    since these validators only need to match once, and any other errors may
+    not be relevant.
+
+    Arguments:
+        errors (collections.Iterable):
+
+            the errors to select from. Do not provide a mixture of
+            errors from different validation attempts (i.e. from
+            different instances or schemas), since it won't produce
+            sensical output.
+
+        key (collections.Callable):
+
+            the key to use when sorting errors. See `relevance` and
+            transitively `by_relevance` for more details (the default is
+            to sort with the defaults of that function). Changing the
+            default is only useful if you want to change the function
+            that rates errors but still want the error context descent
+            done by this function.
+
+    Returns:
+        the best matching error, or ``None`` if the iterable was empty
+
+    .. note::
+
+        This function is a heuristic. Its return value may change for a given
+        set of inputs from version to version if better heuristics are added.
+    """
+    errors = iter(errors)
+    best = next(errors, None)
+    if best is None:
+        return
+    best = max(itertools.chain([best], errors), key=key)
+
+    while best.context:
+        best = min(best.context, key=key)
+    return best

lib/spack/external/_vendoring/jsonschema/schemas/draft3.json

@@ -0,0 +1,199 @@
+{
+    "$schema": "http://json-schema.org/draft-03/schema#",
+    "dependencies": {
+        "exclusiveMaximum": "maximum",
+        "exclusiveMinimum": "minimum"
+    },
+    "id": "http://json-schema.org/draft-03/schema#",
+    "properties": {
+        "$ref": {
+            "format": "uri",
+            "type": "string"
+        },
+        "$schema": {
+            "format": "uri",
+            "type": "string"
+        },
+        "additionalItems": {
+            "default": {},
+            "type": [
+                {
+                    "$ref": "#"
+                },
+                "boolean"
+            ]
+        },
+        "additionalProperties": {
+            "default": {},
+            "type": [
+                {
+                    "$ref": "#"
+                },
+                "boolean"
+            ]
+        },
+        "default": {
+            "type": "any"
+        },
+        "dependencies": {
+            "additionalProperties": {
+                "items": {
+                    "type": "string"
+                },
+                "type": [
+                    "string",
+                    "array",
+                    {
+                        "$ref": "#"
+                    }
+                ]
+            },
+            "default": {},
+            "type": [
+                "string",
+                "array",
+                "object"
+            ]
+        },
+        "description": {
+            "type": "string"
+        },
+        "disallow": {
+            "items": {
+                "type": [
+                    "string",
+                    {
+                        "$ref": "#"
+                    }
+                ]
+            },
+            "type": [
+                "string",
+                "array"
+            ],
+            "uniqueItems": true
+        },
+        "divisibleBy": {
+            "default": 1,
+            "exclusiveMinimum": true,
+            "minimum": 0,
+            "type": "number"
+        },
+        "enum": {
+            "type": "array"
+        },
+        "exclusiveMaximum": {
+            "default": false,
+            "type": "boolean"
+        },
+        "exclusiveMinimum": {
+            "default": false,
+            "type": "boolean"
+        },
+        "extends": {
+            "default": {},
+            "items": {
+                "$ref": "#"
+            },
+            "type": [
+                {
+                    "$ref": "#"
+                },
+                "array"
+            ]
+        },
+        "format": {
+            "type": "string"
+        },
+        "id": {
+            "format": "uri",
+            "type": "string"
+        },
+        "items": {
+            "default": {},
+            "items": {
+                "$ref": "#"
+            },
+            "type": [
+                {
+                    "$ref": "#"
+                },
+                "array"
+            ]
+        },
+        "maxDecimal": {
+            "minimum": 0,
+            "type": "number"
+        },
+        "maxItems": {
+            "minimum": 0,
+            "type": "integer"
+        },
+        "maxLength": {
+            "type": "integer"
+        },
+        "maximum": {
+            "type": "number"
+        },
+        "minItems": {
+            "default": 0,
+            "minimum": 0,
+            "type": "integer"
+        },
+        "minLength": {
+            "default": 0,
+            "minimum": 0,
+            "type": "integer"
+        },
+        "minimum": {
+            "type": "number"
+        },
+        "pattern": {
+            "format": "regex",
+            "type": "string"
+        },
+        "patternProperties": {
+            "additionalProperties": {
+                "$ref": "#"
+            },
+            "default": {},
+            "type": "object"
+        },
+        "properties": {
+            "additionalProperties": {
+                "$ref": "#",
+                "type": "object"
+            },
+            "default": {},
+            "type": "object"
+        },
+        "required": {
+            "default": false,
+            "type": "boolean"
+        },
+        "title": {
+            "type": "string"
+        },
+        "type": {
+            "default": "any",
+            "items": {
+                "type": [
+                    "string",
+                    {
+                        "$ref": "#"
+                    }
+                ]
+            },
+            "type": [
+                "string",
+                "array"
+            ],
+            "uniqueItems": true
+        },
+        "uniqueItems": {
+            "default": false,
+            "type": "boolean"
+        }
+    },
+    "type": "object"
+}

lib/spack/external/_vendoring/jsonschema/schemas/draft4.json

@@ -0,0 +1,222 @@
+{
+    "$schema": "http://json-schema.org/draft-04/schema#",
+    "default": {},
+    "definitions": {
+        "positiveInteger": {
+            "minimum": 0,
+            "type": "integer"
+        },
+        "positiveIntegerDefault0": {
+            "allOf": [
+                {
+                    "$ref": "#/definitions/positiveInteger"
+                },
+                {
+                    "default": 0
+                }
+            ]
+        },
+        "schemaArray": {
+            "items": {
+                "$ref": "#"
+            },
+            "minItems": 1,
+            "type": "array"
+        },
+        "simpleTypes": {
+            "enum": [
+                "array",
+                "boolean",
+                "integer",
+                "null",
+                "number",
+                "object",
+                "string"
+            ]
+        },
+        "stringArray": {
+            "items": {
+                "type": "string"
+            },
+            "minItems": 1,
+            "type": "array",
+            "uniqueItems": true
+        }
+    },
+    "dependencies": {
+        "exclusiveMaximum": [
+            "maximum"
+        ],
+        "exclusiveMinimum": [
+            "minimum"
+        ]
+    },
+    "description": "Core schema meta-schema",
+    "id": "http://json-schema.org/draft-04/schema#",
+    "properties": {
+        "$schema": {
+            "format": "uri",
+            "type": "string"
+        },
+        "additionalItems": {
+            "anyOf": [
+                {
+                    "type": "boolean"
+                },
+                {
+                    "$ref": "#"
+                }
+            ],
+            "default": {}
+        },
+        "additionalProperties": {
+            "anyOf": [
+                {
+                    "type": "boolean"
+                },
+                {
+                    "$ref": "#"
+                }
+            ],
+            "default": {}
+        },
+        "allOf": {
+            "$ref": "#/definitions/schemaArray"
+        },
+        "anyOf": {
+            "$ref": "#/definitions/schemaArray"
+        },
+        "default": {},
+        "definitions": {
+            "additionalProperties": {
+                "$ref": "#"
+            },
+            "default": {},
+            "type": "object"
+        },
+        "dependencies": {
+            "additionalProperties": {
+                "anyOf": [
+                    {
+                        "$ref": "#"
+                    },
+                    {
+                        "$ref": "#/definitions/stringArray"
+                    }
+                ]
+            },
+            "type": "object"
+        },
+        "description": {
+            "type": "string"
+        },
+        "enum": {
+            "type": "array"
+        },
+        "exclusiveMaximum": {
+            "default": false,
+            "type": "boolean"
+        },
+        "exclusiveMinimum": {
+            "default": false,
+            "type": "boolean"
+        },
+        "format": {
+            "type": "string"
+        },
+        "id": {
+            "format": "uri",
+            "type": "string"
+        },
+        "items": {
+            "anyOf": [
+                {
+                    "$ref": "#"
+                },
+                {
+                    "$ref": "#/definitions/schemaArray"
+                }
+            ],
+            "default": {}
+        },
+        "maxItems": {
+            "$ref": "#/definitions/positiveInteger"
+        },
+        "maxLength": {
+            "$ref": "#/definitions/positiveInteger"
+        },
+        "maxProperties": {
+            "$ref": "#/definitions/positiveInteger"
+        },
+        "maximum": {
+            "type": "number"
+        },
+        "minItems": {
+            "$ref": "#/definitions/positiveIntegerDefault0"
+        },
+        "minLength": {
+            "$ref": "#/definitions/positiveIntegerDefault0"
+        },
+        "minProperties": {
+            "$ref": "#/definitions/positiveIntegerDefault0"
+        },
+        "minimum": {
+            "type": "number"
+        },
+        "multipleOf": {
+            "exclusiveMinimum": true,
+            "minimum": 0,
+            "type": "number"
+        },
+        "not": {
+            "$ref": "#"
+        },
+        "oneOf": {
+            "$ref": "#/definitions/schemaArray"
+        },
+        "pattern": {
+            "format": "regex",
+            "type": "string"
+        },
+        "patternProperties": {
+            "additionalProperties": {
+                "$ref": "#"
+            },
+            "default": {},
+            "type": "object"
+        },
+        "properties": {
+            "additionalProperties": {
+                "$ref": "#"
+            },
+            "default": {},
+            "type": "object"
+        },
+        "required": {
+            "$ref": "#/definitions/stringArray"
+        },
+        "title": {
+            "type": "string"
+        },
+        "type": {
+            "anyOf": [
+                {
+                    "$ref": "#/definitions/simpleTypes"
+                },
+                {
+                    "items": {
+                        "$ref": "#/definitions/simpleTypes"
+                    },
+                    "minItems": 1,
+                    "type": "array",
+                    "uniqueItems": true
+                }
+            ]
+        },
+        "uniqueItems": {
+            "default": false,
+            "type": "boolean"
+        }
+    },
+    "type": "object"
+}

lib/spack/external/_vendoring/jsonschema/schemas/draft6.json

@@ -0,0 +1,153 @@
+{
+    "$schema": "http://json-schema.org/draft-06/schema#",
+    "$id": "http://json-schema.org/draft-06/schema#",
+    "title": "Core schema meta-schema",
+    "definitions": {
+        "schemaArray": {
+            "type": "array",
+            "minItems": 1,
+            "items": { "$ref": "#" }
+        },
+        "nonNegativeInteger": {
+            "type": "integer",
+            "minimum": 0
+        },
+        "nonNegativeIntegerDefault0": {
+            "allOf": [
+                { "$ref": "#/definitions/nonNegativeInteger" },
+                { "default": 0 }
+            ]
+        },
+        "simpleTypes": {
+            "enum": [
+                "array",
+                "boolean",
+                "integer",
+                "null",
+                "number",
+                "object",
+                "string"
+            ]
+        },
+        "stringArray": {
+            "type": "array",
+            "items": { "type": "string" },
+            "uniqueItems": true,
+            "default": []
+        }
+    },
+    "type": ["object", "boolean"],
+    "properties": {
+        "$id": {
+            "type": "string",
+            "format": "uri-reference"
+        },
+        "$schema": {
+            "type": "string",
+            "format": "uri"
+        },
+        "$ref": {
+            "type": "string",
+            "format": "uri-reference"
+        },
+        "title": {
+            "type": "string"
+        },
+        "description": {
+            "type": "string"
+        },
+        "default": {},
+        "examples": {
+            "type": "array",
+            "items": {}
+        },
+        "multipleOf": {
+            "type": "number",
+            "exclusiveMinimum": 0
+        },
+        "maximum": {
+            "type": "number"
+        },
+        "exclusiveMaximum": {
+            "type": "number"
+        },
+        "minimum": {
+            "type": "number"
+        },
+        "exclusiveMinimum": {
+            "type": "number"
+        },
+        "maxLength": { "$ref": "#/definitions/nonNegativeInteger" },
+        "minLength": { "$ref": "#/definitions/nonNegativeIntegerDefault0" },
+        "pattern": {
+            "type": "string",
+            "format": "regex"
+        },
+        "additionalItems": { "$ref": "#" },
+        "items": {
+            "anyOf": [
+                { "$ref": "#" },
+                { "$ref": "#/definitions/schemaArray" }
+            ],
+            "default": {}
+        },
+        "maxItems": { "$ref": "#/definitions/nonNegativeInteger" },
+        "minItems": { "$ref": "#/definitions/nonNegativeIntegerDefault0" },
+        "uniqueItems": {
+            "type": "boolean",
+            "default": false
+        },
+        "contains": { "$ref": "#" },
+        "maxProperties": { "$ref": "#/definitions/nonNegativeInteger" },
+        "minProperties": { "$ref": "#/definitions/nonNegativeIntegerDefault0" },
+        "required": { "$ref": "#/definitions/stringArray" },
+        "additionalProperties": { "$ref": "#" },
+        "definitions": {
+            "type": "object",
+            "additionalProperties": { "$ref": "#" },
+            "default": {}
+        },
+        "properties": {
+            "type": "object",
+            "additionalProperties": { "$ref": "#" },
+            "default": {}
+        },
+        "patternProperties": {
+            "type": "object",
+            "additionalProperties": { "$ref": "#" },
+            "propertyNames": { "format": "regex" },
+            "default": {}
+        },
+        "dependencies": {
+            "type": "object",
+            "additionalProperties": {
+                "anyOf": [
+                    { "$ref": "#" },
+                    { "$ref": "#/definitions/stringArray" }
+                ]
+            }
+        },
+        "propertyNames": { "$ref": "#" },
+        "const": {},
+        "enum": {
+            "type": "array"
+        },
+        "type": {
+            "anyOf": [
+                { "$ref": "#/definitions/simpleTypes" },
+                {
+                    "type": "array",
+                    "items": { "$ref": "#/definitions/simpleTypes" },
+                    "minItems": 1,
+                    "uniqueItems": true
+                }
+            ]
+        },
+        "format": { "type": "string" },
+        "allOf": { "$ref": "#/definitions/schemaArray" },
+        "anyOf": { "$ref": "#/definitions/schemaArray" },
+        "oneOf": { "$ref": "#/definitions/schemaArray" },
+        "not": { "$ref": "#" }
+    },
+    "default": {}
+}

lib/spack/external/_vendoring/jsonschema/schemas/draft7.json

@@ -0,0 +1,166 @@
+{
+    "$schema": "http://json-schema.org/draft-07/schema#",
+    "$id": "http://json-schema.org/draft-07/schema#",
+    "title": "Core schema meta-schema",
+    "definitions": {
+        "schemaArray": {
+            "type": "array",
+            "minItems": 1,
+            "items": { "$ref": "#" }
+        },
+        "nonNegativeInteger": {
+            "type": "integer",
+            "minimum": 0
+        },
+        "nonNegativeIntegerDefault0": {
+            "allOf": [
+                { "$ref": "#/definitions/nonNegativeInteger" },
+                { "default": 0 }
+            ]
+        },
+        "simpleTypes": {
+            "enum": [
+                "array",
+                "boolean",
+                "integer",
+                "null",
+                "number",
+                "object",
+                "string"
+            ]
+        },
+        "stringArray": {
+            "type": "array",
+            "items": { "type": "string" },
+            "uniqueItems": true,
+            "default": []
+        }
+    },
+    "type": ["object", "boolean"],
+    "properties": {
+        "$id": {
+            "type": "string",
+            "format": "uri-reference"
+        },
+        "$schema": {
+            "type": "string",
+            "format": "uri"
+        },
+        "$ref": {
+            "type": "string",
+            "format": "uri-reference"
+        },
+        "$comment": {
+            "type": "string"
+        },
+        "title": {
+            "type": "string"
+        },
+        "description": {
+            "type": "string"
+        },
+        "default": true,
+        "readOnly": {
+            "type": "boolean",
+            "default": false
+        },
+        "examples": {
+            "type": "array",
+            "items": true
+        },
+        "multipleOf": {
+            "type": "number",
+            "exclusiveMinimum": 0
+        },
+        "maximum": {
+            "type": "number"
+        },
+        "exclusiveMaximum": {
+            "type": "number"
+        },
+        "minimum": {
+            "type": "number"
+        },
+        "exclusiveMinimum": {
+            "type": "number"
+        },
+        "maxLength": { "$ref": "#/definitions/nonNegativeInteger" },
+        "minLength": { "$ref": "#/definitions/nonNegativeIntegerDefault0" },
+        "pattern": {
+            "type": "string",
+            "format": "regex"
+        },
+        "additionalItems": { "$ref": "#" },
+        "items": {
+            "anyOf": [
+                { "$ref": "#" },
+                { "$ref": "#/definitions/schemaArray" }
+            ],
+            "default": true
+        },
+        "maxItems": { "$ref": "#/definitions/nonNegativeInteger" },
+        "minItems": { "$ref": "#/definitions/nonNegativeIntegerDefault0" },
+        "uniqueItems": {
+            "type": "boolean",
+            "default": false
+        },
+        "contains": { "$ref": "#" },
+        "maxProperties": { "$ref": "#/definitions/nonNegativeInteger" },
+        "minProperties": { "$ref": "#/definitions/nonNegativeIntegerDefault0" },
+        "required": { "$ref": "#/definitions/stringArray" },
+        "additionalProperties": { "$ref": "#" },
+        "definitions": {
+            "type": "object",
+            "additionalProperties": { "$ref": "#" },
+            "default": {}
+        },
+        "properties": {
+            "type": "object",
+            "additionalProperties": { "$ref": "#" },
+            "default": {}
+        },
+        "patternProperties": {
+            "type": "object",
+            "additionalProperties": { "$ref": "#" },
+            "propertyNames": { "format": "regex" },
+            "default": {}
+        },
+        "dependencies": {
+            "type": "object",
+            "additionalProperties": {
+                "anyOf": [
+                    { "$ref": "#" },
+                    { "$ref": "#/definitions/stringArray" }
+                ]
+            }
+        },
+        "propertyNames": { "$ref": "#" },
+        "const": true,
+        "enum": {
+            "type": "array",
+            "items": true
+        },
+        "type": {
+            "anyOf": [
+                { "$ref": "#/definitions/simpleTypes" },
+                {
+                    "type": "array",
+                    "items": { "$ref": "#/definitions/simpleTypes" },
+                    "minItems": 1,
+                    "uniqueItems": true
+                }
+            ]
+        },
+        "format": { "type": "string" },
+        "contentMediaType": { "type": "string" },
+        "contentEncoding": { "type": "string" },
+        "if": {"$ref": "#"},
+        "then": {"$ref": "#"},
+        "else": {"$ref": "#"},
+        "allOf": { "$ref": "#/definitions/schemaArray" },
+        "anyOf": { "$ref": "#/definitions/schemaArray" },
+        "oneOf": { "$ref": "#/definitions/schemaArray" },
+        "not": { "$ref": "#" }
+    },
+    "default": true
+}

lib/spack/external/_vendoring/jsonschema/tests/_helpers.py

@@ -0,0 +1,5 @@
+def bug(issue=None):
+    message = "A known bug."
+    if issue is not None:
+        message += " See issue #{issue}.".format(issue=issue)
+    return message

lib/spack/external/_vendoring/jsonschema/tests/_suite.py

@@ -0,0 +1,239 @@
+"""
+Python representations of the JSON Schema Test Suite tests.
+"""
+
+from functools import partial
+import json
+import os
+import re
+import subprocess
+import sys
+import unittest
+
+from twisted.python.filepath import FilePath
+import attr
+
+from jsonschema.compat import PY3
+from jsonschema.validators import validators
+import jsonschema
+
+
+def _find_suite():
+    root = os.environ.get("JSON_SCHEMA_TEST_SUITE")
+    if root is not None:
+        return FilePath(root)
+
+    root = FilePath(jsonschema.__file__).parent().sibling("json")
+    if not root.isdir():  # pragma: no cover
+        raise ValueError(
+            (
+                "Can't find the JSON-Schema-Test-Suite directory. "
+                "Set the 'JSON_SCHEMA_TEST_SUITE' environment "
+                "variable or run the tests from alongside a checkout "
+                "of the suite."
+            ),
+        )
+    return root
+
+
+@attr.s(hash=True)
+class Suite(object):
+
+    _root = attr.ib(default=attr.Factory(_find_suite))
+
+    def _remotes(self):
+        jsonschema_suite = self._root.descendant(["bin", "jsonschema_suite"])
+        remotes = subprocess.check_output(
+            [sys.executable, jsonschema_suite.path, "remotes"],
+        )
+        return {
+            "http://localhost:1234/" + name: schema
+            for name, schema in json.loads(remotes.decode("utf-8")).items()
+        }
+
+    def benchmark(self, runner):  # pragma: no cover
+        for name in validators:
+            self.version(name=name).benchmark(runner=runner)
+
+    def version(self, name):
+        return Version(
+            name=name,
+            path=self._root.descendant(["tests", name]),
+            remotes=self._remotes(),
+        )
+
+
+@attr.s(hash=True)
+class Version(object):
+
+    _path = attr.ib()
+    _remotes = attr.ib()
+
+    name = attr.ib()
+
+    def benchmark(self, runner, **kwargs):  # pragma: no cover
+        for suite in self.tests():
+            for test in suite:
+                runner.bench_func(
+                    test.fully_qualified_name,
+                    partial(test.validate_ignoring_errors, **kwargs),
+                )
+
+    def tests(self):
+        return (
+            test
+            for child in self._path.globChildren("*.json")
+            for test in self._tests_in(
+                subject=child.basename()[:-5],
+                path=child,
+            )
+        )
+
+    def format_tests(self):
+        path = self._path.descendant(["optional", "format"])
+        return (
+            test
+            for child in path.globChildren("*.json")
+            for test in self._tests_in(
+                subject=child.basename()[:-5],
+                path=child,
+            )
+        )
+
+    def tests_of(self, name):
+        return self._tests_in(
+            subject=name,
+            path=self._path.child(name + ".json"),
+        )
+
+    def optional_tests_of(self, name):
+        return self._tests_in(
+            subject=name,
+            path=self._path.descendant(["optional", name + ".json"]),
+        )
+
+    def to_unittest_testcase(self, *suites, **kwargs):
+        name = kwargs.pop("name", "Test" + self.name.title())
+        methods = {
+            test.method_name: test.to_unittest_method(**kwargs)
+            for suite in suites
+            for tests in suite
+            for test in tests
+        }
+        cls = type(name, (unittest.TestCase,), methods)
+
+        try:
+            cls.__module__ = _someone_save_us_the_module_of_the_caller()
+        except Exception:  # pragma: no cover
+            # We're doing crazy things, so if they go wrong, like a function
+            # behaving differently on some other interpreter, just make them
+            # not happen.
+            pass
+
+        return cls
+
+    def _tests_in(self, subject, path):
+        for each in json.loads(path.getContent().decode("utf-8")):
+            yield (
+                _Test(
+                    version=self,
+                    subject=subject,
+                    case_description=each["description"],
+                    schema=each["schema"],
+                    remotes=self._remotes,
+                    **test
+                ) for test in each["tests"]
+            )
+
+
+@attr.s(hash=True, repr=False)
+class _Test(object):
+
+    version = attr.ib()
+
+    subject = attr.ib()
+    case_description = attr.ib()
+    description = attr.ib()
+
+    data = attr.ib()
+    schema = attr.ib(repr=False)
+
+    valid = attr.ib()
+
+    _remotes = attr.ib()
+
+    def __repr__(self):  # pragma: no cover
+        return "<Test {}>".format(self.fully_qualified_name)
+
+    @property
+    def fully_qualified_name(self):  # pragma: no cover
+        return " > ".join(
+            [
+                self.version.name,
+                self.subject,
+                self.case_description,
+                self.description,
+            ]
+        )
+
+    @property
+    def method_name(self):
+        delimiters = r"[\W\- ]+"
+        name = "test_%s_%s_%s" % (
+            re.sub(delimiters, "_", self.subject),
+            re.sub(delimiters, "_", self.case_description),
+            re.sub(delimiters, "_", self.description),
+        )
+
+        if not PY3:  # pragma: no cover
+            name = name.encode("utf-8")
+        return name
+
+    def to_unittest_method(self, skip=lambda test: None, **kwargs):
+        if self.valid:
+            def fn(this):
+                self.validate(**kwargs)
+        else:
+            def fn(this):
+                with this.assertRaises(jsonschema.ValidationError):
+                    self.validate(**kwargs)
+
+        fn.__name__ = self.method_name
+        reason = skip(self)
+        return unittest.skipIf(reason is not None, reason)(fn)
+
+    def validate(self, Validator, **kwargs):
+        resolver = jsonschema.RefResolver.from_schema(
+            schema=self.schema,
+            store=self._remotes,
+            id_of=Validator.ID_OF,
+        )
+        jsonschema.validate(
+            instance=self.data,
+            schema=self.schema,
+            cls=Validator,
+            resolver=resolver,
+            **kwargs
+        )
+
+    def validate_ignoring_errors(self, Validator):  # pragma: no cover
+        try:
+            self.validate(Validator=Validator)
+        except jsonschema.ValidationError:
+            pass
+
+
+def _someone_save_us_the_module_of_the_caller():
+    """
+    The FQON of the module 2nd stack frames up from here.
+
+    This is intended to allow us to dynamicallly return test case classes that
+    are indistinguishable from being defined in the module that wants them.
+
+    Otherwise, trial will mis-print the FQON, and copy pasting it won't re-run
+    the class that really is running.
+
+    Save us all, this is all so so so so so terrible.
+    """
+
+    return sys._getframe(2).f_globals["__name__"]

lib/spack/external/_vendoring/jsonschema/tests/test_cli.py

@@ -0,0 +1,151 @@
+from unittest import TestCase
+import json
+import subprocess
+import sys
+
+from jsonschema import Draft4Validator, ValidationError, cli, __version__
+from jsonschema.compat import NativeIO
+from jsonschema.exceptions import SchemaError
+
+
+def fake_validator(*errors):
+    errors = list(reversed(errors))
+
+    class FakeValidator(object):
+        def __init__(self, *args, **kwargs):
+            pass
+
+        def iter_errors(self, instance):
+            if errors:
+                return errors.pop()
+            return []
+
+        def check_schema(self, schema):
+            pass
+
+    return FakeValidator
+
+
+class TestParser(TestCase):
+
+    FakeValidator = fake_validator()
+    instance_file = "foo.json"
+    schema_file = "schema.json"
+
+    def setUp(self):
+        cli.open = self.fake_open
+        self.addCleanup(delattr, cli, "open")
+
+    def fake_open(self, path):
+        if path == self.instance_file:
+            contents = ""
+        elif path == self.schema_file:
+            contents = {}
+        else:  # pragma: no cover
+            self.fail("What is {!r}".format(path))
+        return NativeIO(json.dumps(contents))
+
+    def test_find_validator_by_fully_qualified_object_name(self):
+        arguments = cli.parse_args(
+            [
+                "--validator",
+                "jsonschema.tests.test_cli.TestParser.FakeValidator",
+                "--instance", self.instance_file,
+                self.schema_file,
+            ]
+        )
+        self.assertIs(arguments["validator"], self.FakeValidator)
+
+    def test_find_validator_in_jsonschema(self):
+        arguments = cli.parse_args(
+            [
+                "--validator", "Draft4Validator",
+                "--instance", self.instance_file,
+                self.schema_file,
+            ]
+        )
+        self.assertIs(arguments["validator"], Draft4Validator)
+
+
+class TestCLI(TestCase):
+    def test_draft3_schema_draft4_validator(self):
+        stdout, stderr = NativeIO(), NativeIO()
+        with self.assertRaises(SchemaError):
+            cli.run(
+                {
+                    "validator": Draft4Validator,
+                    "schema": {
+                        "anyOf": [
+                            {"minimum": 20},
+                            {"type": "string"},
+                            {"required": True},
+                        ],
+                    },
+                    "instances": [1],
+                    "error_format": "{error.message}",
+                },
+                stdout=stdout,
+                stderr=stderr,
+            )
+
+    def test_successful_validation(self):
+        stdout, stderr = NativeIO(), NativeIO()
+        exit_code = cli.run(
+            {
+                "validator": fake_validator(),
+                "schema": {},
+                "instances": [1],
+                "error_format": "{error.message}",
+            },
+            stdout=stdout,
+            stderr=stderr,
+        )
+        self.assertFalse(stdout.getvalue())
+        self.assertFalse(stderr.getvalue())
+        self.assertEqual(exit_code, 0)
+
+    def test_unsuccessful_validation(self):
+        error = ValidationError("I am an error!", instance=1)
+        stdout, stderr = NativeIO(), NativeIO()
+        exit_code = cli.run(
+            {
+                "validator": fake_validator([error]),
+                "schema": {},
+                "instances": [1],
+                "error_format": "{error.instance} - {error.message}",
+            },
+            stdout=stdout,
+            stderr=stderr,
+        )
+        self.assertFalse(stdout.getvalue())
+        self.assertEqual(stderr.getvalue(), "1 - I am an error!")
+        self.assertEqual(exit_code, 1)
+
+    def test_unsuccessful_validation_multiple_instances(self):
+        first_errors = [
+            ValidationError("9", instance=1),
+            ValidationError("8", instance=1),
+        ]
+        second_errors = [ValidationError("7", instance=2)]
+        stdout, stderr = NativeIO(), NativeIO()
+        exit_code = cli.run(
+            {
+                "validator": fake_validator(first_errors, second_errors),
+                "schema": {},
+                "instances": [1, 2],
+                "error_format": "{error.instance} - {error.message}\t",
+            },
+            stdout=stdout,
+            stderr=stderr,
+        )
+        self.assertFalse(stdout.getvalue())
+        self.assertEqual(stderr.getvalue(), "1 - 9\t1 - 8\t2 - 7\t")
+        self.assertEqual(exit_code, 1)
+
+    def test_version(self):
+        version = subprocess.check_output(
+            [sys.executable, "-m", "jsonschema", "--version"],
+            stderr=subprocess.STDOUT,
+        )
+        version = version.decode("utf-8").strip()
+        self.assertEqual(version, __version__)

lib/spack/external/_vendoring/jsonschema/tests/test_exceptions.py

@@ -0,0 +1,462 @@
+from unittest import TestCase
+import textwrap
+
+from jsonschema import Draft4Validator, exceptions
+from jsonschema.compat import PY3
+
+
+class TestBestMatch(TestCase):
+    def best_match(self, errors):
+        errors = list(errors)
+        best = exceptions.best_match(errors)
+        reversed_best = exceptions.best_match(reversed(errors))
+        msg = "Didn't return a consistent best match!\nGot: {0}\n\nThen: {1}"
+        self.assertEqual(
+            best._contents(), reversed_best._contents(),
+            msg=msg.format(best, reversed_best),
+        )
+        return best
+
+    def test_shallower_errors_are_better_matches(self):
+        validator = Draft4Validator(
+            {
+                "properties": {
+                    "foo": {
+                        "minProperties": 2,
+                        "properties": {"bar": {"type": "object"}},
+                    },
+                },
+            },
+        )
+        best = self.best_match(validator.iter_errors({"foo": {"bar": []}}))
+        self.assertEqual(best.validator, "minProperties")
+
+    def test_oneOf_and_anyOf_are_weak_matches(self):
+        """
+        A property you *must* match is probably better than one you have to
+        match a part of.
+        """
+
+        validator = Draft4Validator(
+            {
+                "minProperties": 2,
+                "anyOf": [{"type": "string"}, {"type": "number"}],
+                "oneOf": [{"type": "string"}, {"type": "number"}],
+            }
+        )
+        best = self.best_match(validator.iter_errors({}))
+        self.assertEqual(best.validator, "minProperties")
+
+    def test_if_the_most_relevant_error_is_anyOf_it_is_traversed(self):
+        """
+        If the most relevant error is an anyOf, then we traverse its context
+        and select the otherwise *least* relevant error, since in this case
+        that means the most specific, deep, error inside the instance.
+
+        I.e. since only one of the schemas must match, we look for the most
+        relevant one.
+        """
+
+        validator = Draft4Validator(
+            {
+                "properties": {
+                    "foo": {
+                        "anyOf": [
+                            {"type": "string"},
+                            {"properties": {"bar": {"type": "array"}}},
+                        ],
+                    },
+                },
+            },
+        )
+        best = self.best_match(validator.iter_errors({"foo": {"bar": 12}}))
+        self.assertEqual(best.validator_value, "array")
+
+    def test_if_the_most_relevant_error_is_oneOf_it_is_traversed(self):
+        """
+        If the most relevant error is an oneOf, then we traverse its context
+        and select the otherwise *least* relevant error, since in this case
+        that means the most specific, deep, error inside the instance.
+
+        I.e. since only one of the schemas must match, we look for the most
+        relevant one.
+        """
+
+        validator = Draft4Validator(
+            {
+                "properties": {
+                    "foo": {
+                        "oneOf": [
+                            {"type": "string"},
+                            {"properties": {"bar": {"type": "array"}}},
+                        ],
+                    },
+                },
+            },
+        )
+        best = self.best_match(validator.iter_errors({"foo": {"bar": 12}}))
+        self.assertEqual(best.validator_value, "array")
+
+    def test_if_the_most_relevant_error_is_allOf_it_is_traversed(self):
+        """
+        Now, if the error is allOf, we traverse but select the *most* relevant
+        error from the context, because all schemas here must match anyways.
+        """
+
+        validator = Draft4Validator(
+            {
+                "properties": {
+                    "foo": {
+                        "allOf": [
+                            {"type": "string"},
+                            {"properties": {"bar": {"type": "array"}}},
+                        ],
+                    },
+                },
+            },
+        )
+        best = self.best_match(validator.iter_errors({"foo": {"bar": 12}}))
+        self.assertEqual(best.validator_value, "string")
+
+    def test_nested_context_for_oneOf(self):
+        validator = Draft4Validator(
+            {
+                "properties": {
+                    "foo": {
+                        "oneOf": [
+                            {"type": "string"},
+                            {
+                                "oneOf": [
+                                    {"type": "string"},
+                                    {
+                                        "properties": {
+                                            "bar": {"type": "array"},
+                                        },
+                                    },
+                                ],
+                            },
+                        ],
+                    },
+                },
+            },
+        )
+        best = self.best_match(validator.iter_errors({"foo": {"bar": 12}}))
+        self.assertEqual(best.validator_value, "array")
+
+    def test_one_error(self):
+        validator = Draft4Validator({"minProperties": 2})
+        error, = validator.iter_errors({})
+        self.assertEqual(
+            exceptions.best_match(validator.iter_errors({})).validator,
+            "minProperties",
+        )
+
+    def test_no_errors(self):
+        validator = Draft4Validator({})
+        self.assertIsNone(exceptions.best_match(validator.iter_errors({})))
+
+
+class TestByRelevance(TestCase):
+    def test_short_paths_are_better_matches(self):
+        shallow = exceptions.ValidationError("Oh no!", path=["baz"])
+        deep = exceptions.ValidationError("Oh yes!", path=["foo", "bar"])
+        match = max([shallow, deep], key=exceptions.relevance)
+        self.assertIs(match, shallow)
+
+        match = max([deep, shallow], key=exceptions.relevance)
+        self.assertIs(match, shallow)
+
+    def test_global_errors_are_even_better_matches(self):
+        shallow = exceptions.ValidationError("Oh no!", path=[])
+        deep = exceptions.ValidationError("Oh yes!", path=["foo"])
+
+        errors = sorted([shallow, deep], key=exceptions.relevance)
+        self.assertEqual(
+            [list(error.path) for error in errors],
+            [["foo"], []],
+        )
+
+        errors = sorted([deep, shallow], key=exceptions.relevance)
+        self.assertEqual(
+            [list(error.path) for error in errors],
+            [["foo"], []],
+        )
+
+    def test_weak_validators_are_lower_priority(self):
+        weak = exceptions.ValidationError("Oh no!", path=[], validator="a")
+        normal = exceptions.ValidationError("Oh yes!", path=[], validator="b")
+
+        best_match = exceptions.by_relevance(weak="a")
+
+        match = max([weak, normal], key=best_match)
+        self.assertIs(match, normal)
+
+        match = max([normal, weak], key=best_match)
+        self.assertIs(match, normal)
+
+    def test_strong_validators_are_higher_priority(self):
+        weak = exceptions.ValidationError("Oh no!", path=[], validator="a")
+        normal = exceptions.ValidationError("Oh yes!", path=[], validator="b")
+        strong = exceptions.ValidationError("Oh fine!", path=[], validator="c")
+
+        best_match = exceptions.by_relevance(weak="a", strong="c")
+
+        match = max([weak, normal, strong], key=best_match)
+        self.assertIs(match, strong)
+
+        match = max([strong, normal, weak], key=best_match)
+        self.assertIs(match, strong)
+
+
+class TestErrorTree(TestCase):
+    def test_it_knows_how_many_total_errors_it_contains(self):
+        # FIXME: https://github.com/Julian/jsonschema/issues/442
+        errors = [
+            exceptions.ValidationError("Something", validator=i)
+            for i in range(8)
+        ]
+        tree = exceptions.ErrorTree(errors)
+        self.assertEqual(tree.total_errors, 8)
+
+    def test_it_contains_an_item_if_the_item_had_an_error(self):
+        errors = [exceptions.ValidationError("a message", path=["bar"])]
+        tree = exceptions.ErrorTree(errors)
+        self.assertIn("bar", tree)
+
+    def test_it_does_not_contain_an_item_if_the_item_had_no_error(self):
+        errors = [exceptions.ValidationError("a message", path=["bar"])]
+        tree = exceptions.ErrorTree(errors)
+        self.assertNotIn("foo", tree)
+
+    def test_validators_that_failed_appear_in_errors_dict(self):
+        error = exceptions.ValidationError("a message", validator="foo")
+        tree = exceptions.ErrorTree([error])
+        self.assertEqual(tree.errors, {"foo": error})
+
+    def test_it_creates_a_child_tree_for_each_nested_path(self):
+        errors = [
+            exceptions.ValidationError("a bar message", path=["bar"]),
+            exceptions.ValidationError("a bar -> 0 message", path=["bar", 0]),
+        ]
+        tree = exceptions.ErrorTree(errors)
+        self.assertIn(0, tree["bar"])
+        self.assertNotIn(1, tree["bar"])
+
+    def test_children_have_their_errors_dicts_built(self):
+        e1, e2 = (
+            exceptions.ValidationError("1", validator="foo", path=["bar", 0]),
+            exceptions.ValidationError("2", validator="quux", path=["bar", 0]),
+        )
+        tree = exceptions.ErrorTree([e1, e2])
+        self.assertEqual(tree["bar"][0].errors, {"foo": e1, "quux": e2})
+
+    def test_multiple_errors_with_instance(self):
+        e1, e2 = (
+            exceptions.ValidationError(
+                "1",
+                validator="foo",
+                path=["bar", "bar2"],
+                instance="i1"),
+            exceptions.ValidationError(
+                "2",
+                validator="quux",
+                path=["foobar", 2],
+                instance="i2"),
+        )
+        exceptions.ErrorTree([e1, e2])
+
+    def test_it_does_not_contain_subtrees_that_are_not_in_the_instance(self):
+        error = exceptions.ValidationError("123", validator="foo", instance=[])
+        tree = exceptions.ErrorTree([error])
+
+        with self.assertRaises(IndexError):
+            tree[0]
+
+    def test_if_its_in_the_tree_anyhow_it_does_not_raise_an_error(self):
+        """
+        If a validator is dumb (like :validator:`required` in draft 3) and
+        refers to a path that isn't in the instance, the tree still properly
+        returns a subtree for that path.
+        """
+
+        error = exceptions.ValidationError(
+            "a message", validator="foo", instance={}, path=["foo"],
+        )
+        tree = exceptions.ErrorTree([error])
+        self.assertIsInstance(tree["foo"], exceptions.ErrorTree)
+
+
+class TestErrorInitReprStr(TestCase):
+    def make_error(self, **kwargs):
+        defaults = dict(
+            message=u"hello",
+            validator=u"type",
+            validator_value=u"string",
+            instance=5,
+            schema={u"type": u"string"},
+        )
+        defaults.update(kwargs)
+        return exceptions.ValidationError(**defaults)
+
+    def assertShows(self, expected, **kwargs):
+        if PY3:  # pragma: no cover
+            expected = expected.replace("u'", "'")
+        expected = textwrap.dedent(expected).rstrip("\n")
+
+        error = self.make_error(**kwargs)
+        message_line, _, rest = str(error).partition("\n")
+        self.assertEqual(message_line, error.message)
+        self.assertEqual(rest, expected)
+
+    def test_it_calls_super_and_sets_args(self):
+        error = self.make_error()
+        self.assertGreater(len(error.args), 1)
+
+    def test_repr(self):
+        self.assertEqual(
+            repr(exceptions.ValidationError(message="Hello!")),
+            "<ValidationError: %r>" % "Hello!",
+        )
+
+    def test_unset_error(self):
+        error = exceptions.ValidationError("message")
+        self.assertEqual(str(error), "message")
+
+        kwargs = {
+            "validator": "type",
+            "validator_value": "string",
+            "instance": 5,
+            "schema": {"type": "string"},
+        }
+        # Just the message should show if any of the attributes are unset
+        for attr in kwargs:
+            k = dict(kwargs)
+            del k[attr]
+            error = exceptions.ValidationError("message", **k)
+            self.assertEqual(str(error), "message")
+
+    def test_empty_paths(self):
+        self.assertShows(
+            """
+            Failed validating u'type' in schema:
+                {u'type': u'string'}
+
+            On instance:
+                5
+            """,
+            path=[],
+            schema_path=[],
+        )
+
+    def test_one_item_paths(self):
+        self.assertShows(
+            """
+            Failed validating u'type' in schema:
+                {u'type': u'string'}
+
+            On instance[0]:
+                5
+            """,
+            path=[0],
+            schema_path=["items"],
+        )
+
+    def test_multiple_item_paths(self):
+        self.assertShows(
+            """
+            Failed validating u'type' in schema[u'items'][0]:
+                {u'type': u'string'}
+
+            On instance[0][u'a']:
+                5
+            """,
+            path=[0, u"a"],
+            schema_path=[u"items", 0, 1],
+        )
+
+    def test_uses_pprint(self):
+        self.assertShows(
+            """
+            Failed validating u'maxLength' in schema:
+                {0: 0,
+                 1: 1,
+                 2: 2,
+                 3: 3,
+                 4: 4,
+                 5: 5,
+                 6: 6,
+                 7: 7,
+                 8: 8,
+                 9: 9,
+                 10: 10,
+                 11: 11,
+                 12: 12,
+                 13: 13,
+                 14: 14,
+                 15: 15,
+                 16: 16,
+                 17: 17,
+                 18: 18,
+                 19: 19}
+
+            On instance:
+                [0,
+                 1,
+                 2,
+                 3,
+                 4,
+                 5,
+                 6,
+                 7,
+                 8,
+                 9,
+                 10,
+                 11,
+                 12,
+                 13,
+                 14,
+                 15,
+                 16,
+                 17,
+                 18,
+                 19,
+                 20,
+                 21,
+                 22,
+                 23,
+                 24]
+            """,
+            instance=list(range(25)),
+            schema=dict(zip(range(20), range(20))),
+            validator=u"maxLength",
+        )
+
+    def test_str_works_with_instances_having_overriden_eq_operator(self):
+        """
+        Check for https://github.com/Julian/jsonschema/issues/164 which
+        rendered exceptions unusable when a `ValidationError` involved
+        instances with an `__eq__` method that returned truthy values.
+        """
+
+        class DontEQMeBro(object):
+            def __eq__(this, other):  # pragma: no cover
+                self.fail("Don't!")
+
+            def __ne__(this, other):  # pragma: no cover
+                self.fail("Don't!")
+
+        instance = DontEQMeBro()
+        error = exceptions.ValidationError(
+            "a message",
+            validator="foo",
+            instance=instance,
+            validator_value="some",
+            schema="schema",
+        )
+        self.assertIn(repr(instance), str(error))
+
+
+class TestHashable(TestCase):
+    def test_hashable(self):
+        set([exceptions.ValidationError("")])
+        set([exceptions.SchemaError("")])

lib/spack/external/_vendoring/jsonschema/tests/test_format.py

@@ -0,0 +1,89 @@
+"""
+Tests for the parts of jsonschema related to the :validator:`format` property.
+"""
+
+from unittest import TestCase
+
+from jsonschema import FormatError, ValidationError, FormatChecker
+from jsonschema.validators import Draft4Validator
+
+
+BOOM = ValueError("Boom!")
+BANG = ZeroDivisionError("Bang!")
+
+
+def boom(thing):
+    if thing == "bang":
+        raise BANG
+    raise BOOM
+
+
+class TestFormatChecker(TestCase):
+    def test_it_can_validate_no_formats(self):
+        checker = FormatChecker(formats=())
+        self.assertFalse(checker.checkers)
+
+    def test_it_raises_a_key_error_for_unknown_formats(self):
+        with self.assertRaises(KeyError):
+            FormatChecker(formats=["o noes"])
+
+    def test_it_can_register_cls_checkers(self):
+        original = dict(FormatChecker.checkers)
+        self.addCleanup(FormatChecker.checkers.pop, "boom")
+        FormatChecker.cls_checks("boom")(boom)
+        self.assertEqual(
+            FormatChecker.checkers,
+            dict(original, boom=(boom, ())),
+        )
+
+    def test_it_can_register_checkers(self):
+        checker = FormatChecker()
+        checker.checks("boom")(boom)
+        self.assertEqual(
+            checker.checkers,
+            dict(FormatChecker.checkers, boom=(boom, ()))
+        )
+
+    def test_it_catches_registered_errors(self):
+        checker = FormatChecker()
+        checker.checks("boom", raises=type(BOOM))(boom)
+
+        with self.assertRaises(FormatError) as cm:
+            checker.check(instance=12, format="boom")
+
+        self.assertIs(cm.exception.cause, BOOM)
+        self.assertIs(cm.exception.__cause__, BOOM)
+
+        # Unregistered errors should not be caught
+        with self.assertRaises(type(BANG)):
+            checker.check(instance="bang", format="boom")
+
+    def test_format_error_causes_become_validation_error_causes(self):
+        checker = FormatChecker()
+        checker.checks("boom", raises=ValueError)(boom)
+        validator = Draft4Validator({"format": "boom"}, format_checker=checker)
+
+        with self.assertRaises(ValidationError) as cm:
+            validator.validate("BOOM")
+
+        self.assertIs(cm.exception.cause, BOOM)
+        self.assertIs(cm.exception.__cause__, BOOM)
+
+    def test_format_checkers_come_with_defaults(self):
+        # This is bad :/ but relied upon.
+        # The docs for quite awhile recommended people do things like
+        # validate(..., format_checker=FormatChecker())
+        # We should change that, but we can't without deprecation...
+        checker = FormatChecker()
+        with self.assertRaises(FormatError):
+            checker.check(instance="not-an-ipv4", format="ipv4")
+
+    def test_repr(self):
+        checker = FormatChecker(formats=())
+        checker.checks("foo")(lambda thing: True)
+        checker.checks("bar")(lambda thing: True)
+        checker.checks("baz")(lambda thing: True)
+        self.assertEqual(
+            repr(checker),
+            "<FormatChecker checkers=['bar', 'baz', 'foo']>",
+        )