externals: add pyrsistent for new jsonschema

Updating `jsonschema` to 3.2.0 requires `pyrsistent`. Adding just the pieces of it
that are needed for `jsonschema`.
This commit is contained in:
Todd Gamblin 2021-12-19 11:17:27 -08:00
parent 04536db387
commit 90592b3cbe
8 changed files with 1387 additions and 0 deletions

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@ -70,6 +70,10 @@ PackageName: py
PackageHomePage: https://pypi.python.org/pypi/py
PackageLicenseDeclared: MIT
PackageName: pyrsistent
PackageHomePage: http://github.com/tobgu/pyrsistent
PackageLicenseDeclared: MIT
PackageName: pytest
PackageHomePage: https://pypi.python.org/pypi/pytest
PackageLicenseDeclared: MIT

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@ -81,6 +81,14 @@
* Note: This packages has been modified:
* https://github.com/pytest-dev/py/pull/186 was backported
pyrsistent
----------
* Homepage: http://github.com/tobgu/pyrsistent/
* Usage: Needed by `jsonschema`
* Version: 0.16.1 (last version supporting Python 2.7)
* Note: We only include the parts needed for `jsonschema`.
pytest
------

22
lib/spack/external/pyrsistent/LICENSE vendored Normal file
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@ -0,0 +1,22 @@
Copyright (c) 2019 Tobias Gustafsson
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.

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@ -0,0 +1,6 @@
# -*- coding: utf-8 -*-
from pyrsistent._pmap import pmap
__all__ = ('pmap',)

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from six import string_types
# enum compat
try:
from enum import Enum
except:
class Enum(object): pass
# no objects will be instances of this class
# collections compat
try:
from collections.abc import (
Container,
Hashable,
Iterable,
Mapping,
Sequence,
Set,
Sized,
)
except ImportError:
from collections import (
Container,
Hashable,
Iterable,
Mapping,
Sequence,
Set,
Sized,
)

460
lib/spack/external/pyrsistent/_pmap.py vendored Normal file
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from ._compat import Mapping, Hashable
from itertools import chain
import six
from pyrsistent._pvector import pvector
from pyrsistent._transformations import transform
class PMap(object):
"""
Persistent map/dict. Tries to follow the same naming conventions as the built in dict where feasible.
Do not instantiate directly, instead use the factory functions :py:func:`m` or :py:func:`pmap` to
create an instance.
Was originally written as a very close copy of the Clojure equivalent but was later rewritten to closer
re-assemble the python dict. This means that a sparse vector (a PVector) of buckets is used. The keys are
hashed and the elements inserted at position hash % len(bucket_vector). Whenever the map size exceeds 2/3 of
the containing vectors size the map is reallocated to a vector of double the size. This is done to avoid
excessive hash collisions.
This structure corresponds most closely to the built in dict type and is intended as a replacement. Where the
semantics are the same (more or less) the same function names have been used but for some cases it is not possible,
for example assignments and deletion of values.
PMap implements the Mapping protocol and is Hashable. It also supports dot-notation for
element access.
Random access and insert is log32(n) where n is the size of the map.
The following are examples of some common operations on persistent maps
>>> m1 = m(a=1, b=3)
>>> m2 = m1.set('c', 3)
>>> m3 = m2.remove('a')
>>> m1
pmap({'b': 3, 'a': 1})
>>> m2
pmap({'c': 3, 'b': 3, 'a': 1})
>>> m3
pmap({'c': 3, 'b': 3})
>>> m3['c']
3
>>> m3.c
3
"""
__slots__ = ('_size', '_buckets', '__weakref__', '_cached_hash')
def __new__(cls, size, buckets):
self = super(PMap, cls).__new__(cls)
self._size = size
self._buckets = buckets
return self
@staticmethod
def _get_bucket(buckets, key):
index = hash(key) % len(buckets)
bucket = buckets[index]
return index, bucket
@staticmethod
def _getitem(buckets, key):
_, bucket = PMap._get_bucket(buckets, key)
if bucket:
for k, v in bucket:
if k == key:
return v
raise KeyError(key)
def __getitem__(self, key):
return PMap._getitem(self._buckets, key)
@staticmethod
def _contains(buckets, key):
_, bucket = PMap._get_bucket(buckets, key)
if bucket:
for k, _ in bucket:
if k == key:
return True
return False
return False
def __contains__(self, key):
return self._contains(self._buckets, key)
get = Mapping.get
def __iter__(self):
return self.iterkeys()
def __getattr__(self, key):
try:
return self[key]
except KeyError:
raise AttributeError(
"{0} has no attribute '{1}'".format(type(self).__name__, key)
)
def iterkeys(self):
for k, _ in self.iteritems():
yield k
# These are more efficient implementations compared to the original
# methods that are based on the keys iterator and then calls the
# accessor functions to access the value for the corresponding key
def itervalues(self):
for _, v in self.iteritems():
yield v
def iteritems(self):
for bucket in self._buckets:
if bucket:
for k, v in bucket:
yield k, v
def values(self):
return pvector(self.itervalues())
def keys(self):
return pvector(self.iterkeys())
def items(self):
return pvector(self.iteritems())
def __len__(self):
return self._size
def __repr__(self):
return 'pmap({0})'.format(str(dict(self)))
def __eq__(self, other):
if self is other:
return True
if not isinstance(other, Mapping):
return NotImplemented
if len(self) != len(other):
return False
if isinstance(other, PMap):
if (hasattr(self, '_cached_hash') and hasattr(other, '_cached_hash')
and self._cached_hash != other._cached_hash):
return False
if self._buckets == other._buckets:
return True
return dict(self.iteritems()) == dict(other.iteritems())
elif isinstance(other, dict):
return dict(self.iteritems()) == other
return dict(self.iteritems()) == dict(six.iteritems(other))
__ne__ = Mapping.__ne__
def __lt__(self, other):
raise TypeError('PMaps are not orderable')
__le__ = __lt__
__gt__ = __lt__
__ge__ = __lt__
def __str__(self):
return self.__repr__()
def __hash__(self):
if not hasattr(self, '_cached_hash'):
self._cached_hash = hash(frozenset(self.iteritems()))
return self._cached_hash
def set(self, key, val):
"""
Return a new PMap with key and val inserted.
>>> m1 = m(a=1, b=2)
>>> m2 = m1.set('a', 3)
>>> m3 = m1.set('c' ,4)
>>> m1
pmap({'b': 2, 'a': 1})
>>> m2
pmap({'b': 2, 'a': 3})
>>> m3
pmap({'c': 4, 'b': 2, 'a': 1})
"""
return self.evolver().set(key, val).persistent()
def remove(self, key):
"""
Return a new PMap without the element specified by key. Raises KeyError if the element
is not present.
>>> m1 = m(a=1, b=2)
>>> m1.remove('a')
pmap({'b': 2})
"""
return self.evolver().remove(key).persistent()
def discard(self, key):
"""
Return a new PMap without the element specified by key. Returns reference to itself
if element is not present.
>>> m1 = m(a=1, b=2)
>>> m1.discard('a')
pmap({'b': 2})
>>> m1 is m1.discard('c')
True
"""
try:
return self.remove(key)
except KeyError:
return self
def update(self, *maps):
"""
Return a new PMap with the items in Mappings inserted. If the same key is present in multiple
maps the rightmost (last) value is inserted.
>>> m1 = m(a=1, b=2)
>>> m1.update(m(a=2, c=3), {'a': 17, 'd': 35})
pmap({'c': 3, 'b': 2, 'a': 17, 'd': 35})
"""
return self.update_with(lambda l, r: r, *maps)
def update_with(self, update_fn, *maps):
"""
Return a new PMap with the items in Mappings maps inserted. If the same key is present in multiple
maps the values will be merged using merge_fn going from left to right.
>>> from operator import add
>>> m1 = m(a=1, b=2)
>>> m1.update_with(add, m(a=2))
pmap({'b': 2, 'a': 3})
The reverse behaviour of the regular merge. Keep the leftmost element instead of the rightmost.
>>> m1 = m(a=1)
>>> m1.update_with(lambda l, r: l, m(a=2), {'a':3})
pmap({'a': 1})
"""
evolver = self.evolver()
for map in maps:
for key, value in map.items():
evolver.set(key, update_fn(evolver[key], value) if key in evolver else value)
return evolver.persistent()
def __add__(self, other):
return self.update(other)
def __reduce__(self):
# Pickling support
return pmap, (dict(self),)
def transform(self, *transformations):
"""
Transform arbitrarily complex combinations of PVectors and PMaps. A transformation
consists of two parts. One match expression that specifies which elements to transform
and one transformation function that performs the actual transformation.
>>> from pyrsistent import freeze, ny
>>> news_paper = freeze({'articles': [{'author': 'Sara', 'content': 'A short article'},
... {'author': 'Steve', 'content': 'A slightly longer article'}],
... 'weather': {'temperature': '11C', 'wind': '5m/s'}})
>>> short_news = news_paper.transform(['articles', ny, 'content'], lambda c: c[:25] + '...' if len(c) > 25 else c)
>>> very_short_news = news_paper.transform(['articles', ny, 'content'], lambda c: c[:15] + '...' if len(c) > 15 else c)
>>> very_short_news.articles[0].content
'A short article'
>>> very_short_news.articles[1].content
'A slightly long...'
When nothing has been transformed the original data structure is kept
>>> short_news is news_paper
True
>>> very_short_news is news_paper
False
>>> very_short_news.articles[0] is news_paper.articles[0]
True
"""
return transform(self, transformations)
def copy(self):
return self
class _Evolver(object):
__slots__ = ('_buckets_evolver', '_size', '_original_pmap')
def __init__(self, original_pmap):
self._original_pmap = original_pmap
self._buckets_evolver = original_pmap._buckets.evolver()
self._size = original_pmap._size
def __getitem__(self, key):
return PMap._getitem(self._buckets_evolver, key)
def __setitem__(self, key, val):
self.set(key, val)
def set(self, key, val):
if len(self._buckets_evolver) < 0.67 * self._size:
self._reallocate(2 * len(self._buckets_evolver))
kv = (key, val)
index, bucket = PMap._get_bucket(self._buckets_evolver, key)
if bucket:
for k, v in bucket:
if k == key:
if v is not val:
new_bucket = [(k2, v2) if k2 != k else (k2, val) for k2, v2 in bucket]
self._buckets_evolver[index] = new_bucket
return self
new_bucket = [kv]
new_bucket.extend(bucket)
self._buckets_evolver[index] = new_bucket
self._size += 1
else:
self._buckets_evolver[index] = [kv]
self._size += 1
return self
def _reallocate(self, new_size):
new_list = new_size * [None]
buckets = self._buckets_evolver.persistent()
for k, v in chain.from_iterable(x for x in buckets if x):
index = hash(k) % new_size
if new_list[index]:
new_list[index].append((k, v))
else:
new_list[index] = [(k, v)]
# A reallocation should always result in a dirty buckets evolver to avoid
# possible loss of elements when doing the reallocation.
self._buckets_evolver = pvector().evolver()
self._buckets_evolver.extend(new_list)
def is_dirty(self):
return self._buckets_evolver.is_dirty()
def persistent(self):
if self.is_dirty():
self._original_pmap = PMap(self._size, self._buckets_evolver.persistent())
return self._original_pmap
def __len__(self):
return self._size
def __contains__(self, key):
return PMap._contains(self._buckets_evolver, key)
def __delitem__(self, key):
self.remove(key)
def remove(self, key):
index, bucket = PMap._get_bucket(self._buckets_evolver, key)
if bucket:
new_bucket = [(k, v) for (k, v) in bucket if k != key]
if len(bucket) > len(new_bucket):
self._buckets_evolver[index] = new_bucket if new_bucket else None
self._size -= 1
return self
raise KeyError('{0}'.format(key))
def evolver(self):
"""
Create a new evolver for this pmap. For a discussion on evolvers in general see the
documentation for the pvector evolver.
Create the evolver and perform various mutating updates to it:
>>> m1 = m(a=1, b=2)
>>> e = m1.evolver()
>>> e['c'] = 3
>>> len(e)
3
>>> del e['a']
The underlying pmap remains the same:
>>> m1
pmap({'b': 2, 'a': 1})
The changes are kept in the evolver. An updated pmap can be created using the
persistent() function on the evolver.
>>> m2 = e.persistent()
>>> m2
pmap({'c': 3, 'b': 2})
The new pmap will share data with the original pmap in the same way that would have
been done if only using operations on the pmap.
"""
return self._Evolver(self)
Mapping.register(PMap)
Hashable.register(PMap)
def _turbo_mapping(initial, pre_size):
if pre_size:
size = pre_size
else:
try:
size = 2 * len(initial) or 8
except Exception:
# Guess we can't figure out the length. Give up on length hinting,
# we can always reallocate later.
size = 8
buckets = size * [None]
if not isinstance(initial, Mapping):
# Make a dictionary of the initial data if it isn't already,
# that will save us some job further down since we can assume no
# key collisions
initial = dict(initial)
for k, v in six.iteritems(initial):
h = hash(k)
index = h % size
bucket = buckets[index]
if bucket:
bucket.append((k, v))
else:
buckets[index] = [(k, v)]
return PMap(len(initial), pvector().extend(buckets))
_EMPTY_PMAP = _turbo_mapping({}, 0)
def pmap(initial={}, pre_size=0):
"""
Create new persistent map, inserts all elements in initial into the newly created map.
The optional argument pre_size may be used to specify an initial size of the underlying bucket vector. This
may have a positive performance impact in the cases where you know beforehand that a large number of elements
will be inserted into the map eventually since it will reduce the number of reallocations required.
>>> pmap({'a': 13, 'b': 14})
pmap({'b': 14, 'a': 13})
"""
if not initial:
return _EMPTY_PMAP
return _turbo_mapping(initial, pre_size)
def m(**kwargs):
"""
Creates a new persitent map. Inserts all key value arguments into the newly created map.
>>> m(a=13, b=14)
pmap({'b': 14, 'a': 13})
"""
return pmap(kwargs)

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from abc import abstractmethod, ABCMeta
from ._compat import Sequence, Hashable
from numbers import Integral
import operator
import six
from pyrsistent._transformations import transform
def _bitcount(val):
return bin(val).count("1")
BRANCH_FACTOR = 32
BIT_MASK = BRANCH_FACTOR - 1
SHIFT = _bitcount(BIT_MASK)
def compare_pvector(v, other, operator):
return operator(v.tolist(), other.tolist() if isinstance(other, PVector) else other)
def _index_or_slice(index, stop):
if stop is None:
return index
return slice(index, stop)
class PythonPVector(object):
"""
Support structure for PVector that implements structural sharing for vectors using a trie.
"""
__slots__ = ('_count', '_shift', '_root', '_tail', '_tail_offset', '__weakref__')
def __new__(cls, count, shift, root, tail):
self = super(PythonPVector, cls).__new__(cls)
self._count = count
self._shift = shift
self._root = root
self._tail = tail
# Derived attribute stored for performance
self._tail_offset = self._count - len(self._tail)
return self
def __len__(self):
return self._count
def __getitem__(self, index):
if isinstance(index, slice):
# There are more conditions than the below where it would be OK to
# return ourselves, implement those...
if index.start is None and index.stop is None and index.step is None:
return self
# This is a bit nasty realizing the whole structure as a list before
# slicing it but it is the fastest way I've found to date, and it's easy :-)
return _EMPTY_PVECTOR.extend(self.tolist()[index])
if index < 0:
index += self._count
return PythonPVector._node_for(self, index)[index & BIT_MASK]
def __add__(self, other):
return self.extend(other)
def __repr__(self):
return 'pvector({0})'.format(str(self.tolist()))
def __str__(self):
return self.__repr__()
def __iter__(self):
# This is kind of lazy and will produce some memory overhead but it is the fasted method
# by far of those tried since it uses the speed of the built in python list directly.
return iter(self.tolist())
def __ne__(self, other):
return not self.__eq__(other)
def __eq__(self, other):
return self is other or (hasattr(other, '__len__') and self._count == len(other)) and compare_pvector(self, other, operator.eq)
def __gt__(self, other):
return compare_pvector(self, other, operator.gt)
def __lt__(self, other):
return compare_pvector(self, other, operator.lt)
def __ge__(self, other):
return compare_pvector(self, other, operator.ge)
def __le__(self, other):
return compare_pvector(self, other, operator.le)
def __mul__(self, times):
if times <= 0 or self is _EMPTY_PVECTOR:
return _EMPTY_PVECTOR
if times == 1:
return self
return _EMPTY_PVECTOR.extend(times * self.tolist())
__rmul__ = __mul__
def _fill_list(self, node, shift, the_list):
if shift:
shift -= SHIFT
for n in node:
self._fill_list(n, shift, the_list)
else:
the_list.extend(node)
def tolist(self):
"""
The fastest way to convert the vector into a python list.
"""
the_list = []
self._fill_list(self._root, self._shift, the_list)
the_list.extend(self._tail)
return the_list
def _totuple(self):
"""
Returns the content as a python tuple.
"""
return tuple(self.tolist())
def __hash__(self):
# Taking the easy way out again...
return hash(self._totuple())
def transform(self, *transformations):
return transform(self, transformations)
def __reduce__(self):
# Pickling support
return pvector, (self.tolist(),)
def mset(self, *args):
if len(args) % 2:
raise TypeError("mset expected an even number of arguments")
evolver = self.evolver()
for i in range(0, len(args), 2):
evolver[args[i]] = args[i+1]
return evolver.persistent()
class Evolver(object):
__slots__ = ('_count', '_shift', '_root', '_tail', '_tail_offset', '_dirty_nodes',
'_extra_tail', '_cached_leafs', '_orig_pvector')
def __init__(self, v):
self._reset(v)
def __getitem__(self, index):
if not isinstance(index, Integral):
raise TypeError("'%s' object cannot be interpreted as an index" % type(index).__name__)
if index < 0:
index += self._count + len(self._extra_tail)
if self._count <= index < self._count + len(self._extra_tail):
return self._extra_tail[index - self._count]
return PythonPVector._node_for(self, index)[index & BIT_MASK]
def _reset(self, v):
self._count = v._count
self._shift = v._shift
self._root = v._root
self._tail = v._tail
self._tail_offset = v._tail_offset
self._dirty_nodes = {}
self._cached_leafs = {}
self._extra_tail = []
self._orig_pvector = v
def append(self, element):
self._extra_tail.append(element)
return self
def extend(self, iterable):
self._extra_tail.extend(iterable)
return self
def set(self, index, val):
self[index] = val
return self
def __setitem__(self, index, val):
if not isinstance(index, Integral):
raise TypeError("'%s' object cannot be interpreted as an index" % type(index).__name__)
if index < 0:
index += self._count + len(self._extra_tail)
if 0 <= index < self._count:
node = self._cached_leafs.get(index >> SHIFT)
if node:
node[index & BIT_MASK] = val
elif index >= self._tail_offset:
if id(self._tail) not in self._dirty_nodes:
self._tail = list(self._tail)
self._dirty_nodes[id(self._tail)] = True
self._cached_leafs[index >> SHIFT] = self._tail
self._tail[index & BIT_MASK] = val
else:
self._root = self._do_set(self._shift, self._root, index, val)
elif self._count <= index < self._count + len(self._extra_tail):
self._extra_tail[index - self._count] = val
elif index == self._count + len(self._extra_tail):
self._extra_tail.append(val)
else:
raise IndexError("Index out of range: %s" % (index,))
def _do_set(self, level, node, i, val):
if id(node) in self._dirty_nodes:
ret = node
else:
ret = list(node)
self._dirty_nodes[id(ret)] = True
if level == 0:
ret[i & BIT_MASK] = val
self._cached_leafs[i >> SHIFT] = ret
else:
sub_index = (i >> level) & BIT_MASK # >>>
ret[sub_index] = self._do_set(level - SHIFT, node[sub_index], i, val)
return ret
def delete(self, index):
del self[index]
return self
def __delitem__(self, key):
if self._orig_pvector:
# All structural sharing bets are off, base evolver on _extra_tail only
l = PythonPVector(self._count, self._shift, self._root, self._tail).tolist()
l.extend(self._extra_tail)
self._reset(_EMPTY_PVECTOR)
self._extra_tail = l
del self._extra_tail[key]
def persistent(self):
result = self._orig_pvector
if self.is_dirty():
result = PythonPVector(self._count, self._shift, self._root, self._tail).extend(self._extra_tail)
self._reset(result)
return result
def __len__(self):
return self._count + len(self._extra_tail)
def is_dirty(self):
return bool(self._dirty_nodes or self._extra_tail)
def evolver(self):
return PythonPVector.Evolver(self)
def set(self, i, val):
# This method could be implemented by a call to mset() but doing so would cause
# a ~5 X performance penalty on PyPy (considered the primary platform for this implementation
# of PVector) so we're keeping this implementation for now.
if not isinstance(i, Integral):
raise TypeError("'%s' object cannot be interpreted as an index" % type(i).__name__)
if i < 0:
i += self._count
if 0 <= i < self._count:
if i >= self._tail_offset:
new_tail = list(self._tail)
new_tail[i & BIT_MASK] = val
return PythonPVector(self._count, self._shift, self._root, new_tail)
return PythonPVector(self._count, self._shift, self._do_set(self._shift, self._root, i, val), self._tail)
if i == self._count:
return self.append(val)
raise IndexError("Index out of range: %s" % (i,))
def _do_set(self, level, node, i, val):
ret = list(node)
if level == 0:
ret[i & BIT_MASK] = val
else:
sub_index = (i >> level) & BIT_MASK # >>>
ret[sub_index] = self._do_set(level - SHIFT, node[sub_index], i, val)
return ret
@staticmethod
def _node_for(pvector_like, i):
if 0 <= i < pvector_like._count:
if i >= pvector_like._tail_offset:
return pvector_like._tail
node = pvector_like._root
for level in range(pvector_like._shift, 0, -SHIFT):
node = node[(i >> level) & BIT_MASK] # >>>
return node
raise IndexError("Index out of range: %s" % (i,))
def _create_new_root(self):
new_shift = self._shift
# Overflow root?
if (self._count >> SHIFT) > (1 << self._shift): # >>>
new_root = [self._root, self._new_path(self._shift, self._tail)]
new_shift += SHIFT
else:
new_root = self._push_tail(self._shift, self._root, self._tail)
return new_root, new_shift
def append(self, val):
if len(self._tail) < BRANCH_FACTOR:
new_tail = list(self._tail)
new_tail.append(val)
return PythonPVector(self._count + 1, self._shift, self._root, new_tail)
# Full tail, push into tree
new_root, new_shift = self._create_new_root()
return PythonPVector(self._count + 1, new_shift, new_root, [val])
def _new_path(self, level, node):
if level == 0:
return node
return [self._new_path(level - SHIFT, node)]
def _mutating_insert_tail(self):
self._root, self._shift = self._create_new_root()
self._tail = []
def _mutating_fill_tail(self, offset, sequence):
max_delta_len = BRANCH_FACTOR - len(self._tail)
delta = sequence[offset:offset + max_delta_len]
self._tail.extend(delta)
delta_len = len(delta)
self._count += delta_len
return offset + delta_len
def _mutating_extend(self, sequence):
offset = 0
sequence_len = len(sequence)
while offset < sequence_len:
offset = self._mutating_fill_tail(offset, sequence)
if len(self._tail) == BRANCH_FACTOR:
self._mutating_insert_tail()
self._tail_offset = self._count - len(self._tail)
def extend(self, obj):
# Mutates the new vector directly for efficiency but that's only an
# implementation detail, once it is returned it should be considered immutable
l = obj.tolist() if isinstance(obj, PythonPVector) else list(obj)
if l:
new_vector = self.append(l[0])
new_vector._mutating_extend(l[1:])
return new_vector
return self
def _push_tail(self, level, parent, tail_node):
"""
if parent is leaf, insert node,
else does it map to an existing child? ->
node_to_insert = push node one more level
else alloc new path
return node_to_insert placed in copy of parent
"""
ret = list(parent)
if level == SHIFT:
ret.append(tail_node)
return ret
sub_index = ((self._count - 1) >> level) & BIT_MASK # >>>
if len(parent) > sub_index:
ret[sub_index] = self._push_tail(level - SHIFT, parent[sub_index], tail_node)
return ret
ret.append(self._new_path(level - SHIFT, tail_node))
return ret
def index(self, value, *args, **kwargs):
return self.tolist().index(value, *args, **kwargs)
def count(self, value):
return self.tolist().count(value)
def delete(self, index, stop=None):
l = self.tolist()
del l[_index_or_slice(index, stop)]
return _EMPTY_PVECTOR.extend(l)
def remove(self, value):
l = self.tolist()
l.remove(value)
return _EMPTY_PVECTOR.extend(l)
@six.add_metaclass(ABCMeta)
class PVector(object):
"""
Persistent vector implementation. Meant as a replacement for the cases where you would normally
use a Python list.
Do not instantiate directly, instead use the factory functions :py:func:`v` and :py:func:`pvector` to
create an instance.
Heavily influenced by the persistent vector available in Clojure. Initially this was more or
less just a port of the Java code for the Clojure vector. It has since been modified and to
some extent optimized for usage in Python.
The vector is organized as a trie, any mutating method will return a new vector that contains the changes. No
updates are done to the original vector. Structural sharing between vectors are applied where possible to save
space and to avoid making complete copies.
This structure corresponds most closely to the built in list type and is intended as a replacement. Where the
semantics are the same (more or less) the same function names have been used but for some cases it is not possible,
for example assignments.
The PVector implements the Sequence protocol and is Hashable.
Inserts are amortized O(1). Random access is log32(n) where n is the size of the vector.
The following are examples of some common operations on persistent vectors:
>>> p = v(1, 2, 3)
>>> p2 = p.append(4)
>>> p3 = p2.extend([5, 6, 7])
>>> p
pvector([1, 2, 3])
>>> p2
pvector([1, 2, 3, 4])
>>> p3
pvector([1, 2, 3, 4, 5, 6, 7])
>>> p3[5]
6
>>> p.set(1, 99)
pvector([1, 99, 3])
>>>
"""
@abstractmethod
def __len__(self):
"""
>>> len(v(1, 2, 3))
3
"""
@abstractmethod
def __getitem__(self, index):
"""
Get value at index. Full slicing support.
>>> v1 = v(5, 6, 7, 8)
>>> v1[2]
7
>>> v1[1:3]
pvector([6, 7])
"""
@abstractmethod
def __add__(self, other):
"""
>>> v1 = v(1, 2)
>>> v2 = v(3, 4)
>>> v1 + v2
pvector([1, 2, 3, 4])
"""
@abstractmethod
def __mul__(self, times):
"""
>>> v1 = v(1, 2)
>>> 3 * v1
pvector([1, 2, 1, 2, 1, 2])
"""
@abstractmethod
def __hash__(self):
"""
>>> v1 = v(1, 2, 3)
>>> v2 = v(1, 2, 3)
>>> hash(v1) == hash(v2)
True
"""
@abstractmethod
def evolver(self):
"""
Create a new evolver for this pvector. The evolver acts as a mutable view of the vector
with "transaction like" semantics. No part of the underlying vector i updated, it is still
fully immutable. Furthermore multiple evolvers created from the same pvector do not
interfere with each other.
You may want to use an evolver instead of working directly with the pvector in the
following cases:
* Multiple updates are done to the same vector and the intermediate results are of no
interest. In this case using an evolver may be a more efficient and easier to work with.
* You need to pass a vector into a legacy function or a function that you have no control
over which performs in place mutations of lists. In this case pass an evolver instance
instead and then create a new pvector from the evolver once the function returns.
The following example illustrates a typical workflow when working with evolvers. It also
displays most of the API (which i kept small by design, you should not be tempted to
use evolvers in excess ;-)).
Create the evolver and perform various mutating updates to it:
>>> v1 = v(1, 2, 3, 4, 5)
>>> e = v1.evolver()
>>> e[1] = 22
>>> _ = e.append(6)
>>> _ = e.extend([7, 8, 9])
>>> e[8] += 1
>>> len(e)
9
The underlying pvector remains the same:
>>> v1
pvector([1, 2, 3, 4, 5])
The changes are kept in the evolver. An updated pvector can be created using the
persistent() function on the evolver.
>>> v2 = e.persistent()
>>> v2
pvector([1, 22, 3, 4, 5, 6, 7, 8, 10])
The new pvector will share data with the original pvector in the same way that would have
been done if only using operations on the pvector.
"""
@abstractmethod
def mset(self, *args):
"""
Return a new vector with elements in specified positions replaced by values (multi set).
Elements on even positions in the argument list are interpreted as indexes while
elements on odd positions are considered values.
>>> v1 = v(1, 2, 3)
>>> v1.mset(0, 11, 2, 33)
pvector([11, 2, 33])
"""
@abstractmethod
def set(self, i, val):
"""
Return a new vector with element at position i replaced with val. The original vector remains unchanged.
Setting a value one step beyond the end of the vector is equal to appending. Setting beyond that will
result in an IndexError.
>>> v1 = v(1, 2, 3)
>>> v1.set(1, 4)
pvector([1, 4, 3])
>>> v1.set(3, 4)
pvector([1, 2, 3, 4])
>>> v1.set(-1, 4)
pvector([1, 2, 4])
"""
@abstractmethod
def append(self, val):
"""
Return a new vector with val appended.
>>> v1 = v(1, 2)
>>> v1.append(3)
pvector([1, 2, 3])
"""
@abstractmethod
def extend(self, obj):
"""
Return a new vector with all values in obj appended to it. Obj may be another
PVector or any other Iterable.
>>> v1 = v(1, 2, 3)
>>> v1.extend([4, 5])
pvector([1, 2, 3, 4, 5])
"""
@abstractmethod
def index(self, value, *args, **kwargs):
"""
Return first index of value. Additional indexes may be supplied to limit the search to a
sub range of the vector.
>>> v1 = v(1, 2, 3, 4, 3)
>>> v1.index(3)
2
>>> v1.index(3, 3, 5)
4
"""
@abstractmethod
def count(self, value):
"""
Return the number of times that value appears in the vector.
>>> v1 = v(1, 4, 3, 4)
>>> v1.count(4)
2
"""
@abstractmethod
def transform(self, *transformations):
"""
Transform arbitrarily complex combinations of PVectors and PMaps. A transformation
consists of two parts. One match expression that specifies which elements to transform
and one transformation function that performs the actual transformation.
>>> from pyrsistent import freeze, ny
>>> news_paper = freeze({'articles': [{'author': 'Sara', 'content': 'A short article'},
... {'author': 'Steve', 'content': 'A slightly longer article'}],
... 'weather': {'temperature': '11C', 'wind': '5m/s'}})
>>> short_news = news_paper.transform(['articles', ny, 'content'], lambda c: c[:25] + '...' if len(c) > 25 else c)
>>> very_short_news = news_paper.transform(['articles', ny, 'content'], lambda c: c[:15] + '...' if len(c) > 15 else c)
>>> very_short_news.articles[0].content
'A short article'
>>> very_short_news.articles[1].content
'A slightly long...'
When nothing has been transformed the original data structure is kept
>>> short_news is news_paper
True
>>> very_short_news is news_paper
False
>>> very_short_news.articles[0] is news_paper.articles[0]
True
"""
@abstractmethod
def delete(self, index, stop=None):
"""
Delete a portion of the vector by index or range.
>>> v1 = v(1, 2, 3, 4, 5)
>>> v1.delete(1)
pvector([1, 3, 4, 5])
>>> v1.delete(1, 3)
pvector([1, 4, 5])
"""
@abstractmethod
def remove(self, value):
"""
Remove the first occurrence of a value from the vector.
>>> v1 = v(1, 2, 3, 2, 1)
>>> v2 = v1.remove(1)
>>> v2
pvector([2, 3, 2, 1])
>>> v2.remove(1)
pvector([2, 3, 2])
"""
_EMPTY_PVECTOR = PythonPVector(0, SHIFT, [], [])
PVector.register(PythonPVector)
Sequence.register(PVector)
Hashable.register(PVector)
def python_pvector(iterable=()):
"""
Create a new persistent vector containing the elements in iterable.
>>> v1 = pvector([1, 2, 3])
>>> v1
pvector([1, 2, 3])
"""
return _EMPTY_PVECTOR.extend(iterable)
try:
# Use the C extension as underlying trie implementation if it is available
import os
if os.environ.get('PYRSISTENT_NO_C_EXTENSION'):
pvector = python_pvector
else:
from pvectorc import pvector
PVector.register(type(pvector()))
except ImportError:
pvector = python_pvector
def v(*elements):
"""
Create a new persistent vector containing all parameters to this function.
>>> v1 = v(1, 2, 3)
>>> v1
pvector([1, 2, 3])
"""
return pvector(elements)

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@ -0,0 +1,143 @@
import re
import six
try:
from inspect import Parameter, signature
except ImportError:
signature = None
try:
from inspect import getfullargspec as getargspec
except ImportError:
from inspect import getargspec
_EMPTY_SENTINEL = object()
def inc(x):
""" Add one to the current value """
return x + 1
def dec(x):
""" Subtract one from the current value """
return x - 1
def discard(evolver, key):
""" Discard the element and returns a structure without the discarded elements """
try:
del evolver[key]
except KeyError:
pass
# Matchers
def rex(expr):
""" Regular expression matcher to use together with transform functions """
r = re.compile(expr)
return lambda key: isinstance(key, six.string_types) and r.match(key)
def ny(_):
""" Matcher that matches any value """
return True
# Support functions
def _chunks(l, n):
for i in range(0, len(l), n):
yield l[i:i + n]
def transform(structure, transformations):
r = structure
for path, command in _chunks(transformations, 2):
r = _do_to_path(r, path, command)
return r
def _do_to_path(structure, path, command):
if not path:
return command(structure) if callable(command) else command
kvs = _get_keys_and_values(structure, path[0])
return _update_structure(structure, kvs, path[1:], command)
def _items(structure):
try:
return structure.items()
except AttributeError:
# Support wider range of structures by adding a transform_items() or similar?
return list(enumerate(structure))
def _get(structure, key, default):
try:
if hasattr(structure, '__getitem__'):
return structure[key]
return getattr(structure, key)
except (IndexError, KeyError):
return default
def _get_keys_and_values(structure, key_spec):
if callable(key_spec):
# Support predicates as callable objects in the path
arity = _get_arity(key_spec)
if arity == 1:
# Unary predicates are called with the "key" of the path
# - eg a key in a mapping, an index in a sequence.
return [(k, v) for k, v in _items(structure) if key_spec(k)]
elif arity == 2:
# Binary predicates are called with the key and the corresponding
# value.
return [(k, v) for k, v in _items(structure) if key_spec(k, v)]
else:
# Other arities are an error.
raise ValueError(
"callable in transform path must take 1 or 2 arguments"
)
# Non-callables are used as-is as a key.
return [(key_spec, _get(structure, key_spec, _EMPTY_SENTINEL))]
if signature is None:
def _get_arity(f):
argspec = getargspec(f)
return len(argspec.args) - len(argspec.defaults or ())
else:
def _get_arity(f):
return sum(
1
for p
in signature(f).parameters.values()
if p.default is Parameter.empty
and p.kind in (Parameter.POSITIONAL_ONLY, Parameter.POSITIONAL_OR_KEYWORD)
)
def _update_structure(structure, kvs, path, command):
from pyrsistent._pmap import pmap
e = structure.evolver()
if not path and command is discard:
# Do this in reverse to avoid index problems with vectors. See #92.
for k, v in reversed(kvs):
discard(e, k)
else:
for k, v in kvs:
is_empty = False
if v is _EMPTY_SENTINEL:
# Allow expansion of structure but make sure to cover the case
# when an empty pmap is added as leaf node. See #154.
is_empty = True
v = pmap()
result = _do_to_path(v, path, command)
if result is not v or is_empty:
e[k] = result
return e.persistent()