Tk/Tcl packages: speed up file search (#35902)

var/spack/repos/builtin/packages/tcl/package.py

@@ -5,6 +5,8 @@
 
 import os
 
+from llnl.util.filesystem import find_first
+
 from spack.package import *
 from spack.util.environment import is_system_path
 
@@ -93,6 +95,18 @@ def command(self):
             os.path.realpath(self.prefix.bin.join("tclsh{0}".format(self.version.up_to(2))))
         )
 
+    def _find_script_dir(self):
+        # Put more-specific prefixes first
+        check_prefixes = [
+            join_path(self.prefix, "share", "tcl{0}".format(self.version.up_to(2))),
+            self.prefix,
+        ]
+        for prefix in check_prefixes:
+            result = find_first(prefix, "init.tcl")
+            if result:
+                return os.path.dirname(result)
+        raise RuntimeError("Cannot locate init.tcl")
+
     def setup_run_environment(self, env):
         """Set TCL_LIBRARY to the directory containing init.tcl.
 
@@ -102,7 +116,7 @@ def setup_run_environment(self, env):
         """
         # When using tkinter from within spack provided python+tkinter,
         # python will not be able to find Tcl unless TCL_LIBRARY is set.
-        env.set("TCL_LIBRARY", os.path.dirname(sorted(find(self.prefix, "init.tcl"))[0]))
+        env.set("TCL_LIBRARY", self._find_script_dir())
 
     def setup_dependent_build_environment(self, env, dependent_spec):
         """Set TCL_LIBRARY to the directory containing init.tcl.
@@ -114,7 +128,7 @@ def setup_dependent_build_environment(self, env, dependent_spec):
         * https://wiki.tcl-lang.org/page/TCL_LIBRARY
         * https://wiki.tcl-lang.org/page/TCLLIBPATH
         """
-        env.set("TCL_LIBRARY", os.path.dirname(sorted(find(self.prefix, "init.tcl"))[0]))
+        env.set("TCL_LIBRARY", self._find_script_dir())
 
         # If we set TCLLIBPATH, we must also ensure that the corresponding
         # tcl is found in the build environment. This to prevent cases

var/spack/repos/builtin/packages/tk/package.py

@@ -5,6 +5,8 @@
 
 import os
 
+from llnl.util.filesystem import find_first
+
 from spack.package import *
 
 
@@ -118,6 +120,18 @@ def libs(self):
             ["libtk{0}".format(self.version.up_to(2))], root=self.prefix, recursive=True
         )
 
+    def _find_script_dir(self):
+        # Put more-specific prefixes first
+        check_prefixes = [
+            join_path(self.prefix, "share", "tk{0}".format(self.version.up_to(2))),
+            self.prefix,
+        ]
+        for prefix in check_prefixes:
+            result = find_first(prefix, "tk.tcl")
+            if result:
+                return os.path.dirname(result)
+        raise RuntimeError("Cannot locate tk.tcl")
+
     def setup_run_environment(self, env):
         """Set TK_LIBRARY to the directory containing tk.tcl.
 
@@ -127,7 +141,7 @@ def setup_run_environment(self, env):
         """
         # When using tkinter from within spack provided python+tkinter,
         # python will not be able to find Tk unless TK_LIBRARY is set.
-        env.set("TK_LIBRARY", os.path.dirname(sorted(find(self.prefix, "tk.tcl"))[0]))
+        env.set("TK_LIBRARY", self._find_script_dir())
 
     def setup_dependent_build_environment(self, env, dependent_spec):
         """Set TK_LIBRARY to the directory containing tk.tcl.
@@ -136,4 +150,4 @@ def setup_dependent_build_environment(self, env, dependent_spec):
 
         * https://www.tcl-lang.org/man/tcl/TkCmd/tkvars.htm
         """
-        env.set("TK_LIBRARY", os.path.dirname(sorted(find(self.prefix, "tk.tcl"))[0]))
+        env.set("TK_LIBRARY", self._find_script_dir())