Add support for a toolpath for Environments.

4 files changed, 33 insertions, 12 deletions

diff --git a/src/CHANGES.txt b/src/CHANGES.txt
index 1043b50..2b598ae 100644
--- a/src/CHANGES.txt
+++ b/src/CHANGES.txt
@@ -25,6 +25,9 @@ RELEASE 0.95 - XXX
 
   - Fix a problem with the msvc tool with Python versions prior to 2.3.
 
+  - Add support for a "toolpath" Tool() and Environment keyword that
+    allows Tool modules to be found in specified local directories.
+
   From Chris Burghart:
 
   - Fix the ability to save/restore a PackageOption to a file.
diff --git a/src/engine/SCons/Environment.py b/src/engine/SCons/Environment.py
index 26be483..6afa69f 100644
--- a/src/engine/SCons/Environment.py
+++ b/src/engine/SCons/Environment.py
@@ -109,12 +109,13 @@ def our_deepcopy(x):
        copy = x
    return copy
 
-def apply_tools(env, tools):
+def apply_tools(env, tools, toolpath):
     if tools:
         for tool in tools:
             if SCons.Util.is_String(tool):
-                tool = SCons.Tool.Tool(tool)
-            tool(env)
+                env.Tool(tool, toolpath)
+            else:
+                tool(env)
 
 class BuilderWrapper:
     """Wrapper class that associates an environment with a Builder at
@@ -207,6 +208,7 @@ class Base:
     def __init__(self,
                  platform=None,
                  tools=None,
+                 toolpath=[],
                  options=None,
                  **kw):
         self.fs = SCons.Node.FS.default_fs
@@ -238,7 +240,7 @@ class Base:
             tools = self._dict.get('TOOLS', None)
             if tools is None:
                 tools = ['default']
-        apply_tools(self, tools)
+        apply_tools(self, tools, toolpath)
 
         # Reapply the passed in variables after calling the tools,
         # since they should overide anything set by the tools:
@@ -461,7 +463,7 @@ class Base:
 
         self._dict[envname][name] = nv
 
-    def Copy(self, tools=None, **kw):
+    def Copy(self, tools=None, toolpath=[], **kw):
         """Return a copy of a construction Environment.  The
         copy is like a Python "deep copy"--that is, independent
         copies are made recursively of each objects--except that
@@ -477,7 +479,7 @@ class Base:
         except KeyError:
             pass
         
-        apply_tools(clone, tools)
+        apply_tools(clone, tools, toolpath)
 
         # Apply passed-in variables after the new tools.
         apply(clone.Replace, (), kw)
@@ -666,9 +668,9 @@ class Base:
             name = name[:-len(old_suffix)]
         return os.path.join(dir, new_prefix+name+new_suffix)
 
-    def Tool(self, tool):
+    def Tool(self, tool, toolpath=[]):
         tool = self.subst(tool)
-        return SCons.Tool.Tool(tool)(self)
+        return SCons.Tool.Tool(tool, map(self.subst, toolpath))(self)
 
     def WhereIs(self, prog, path=None, pathext=None):
         """Find prog in the path.  
diff --git a/src/engine/SCons/EnvironmentTests.py b/src/engine/SCons/EnvironmentTests.py
index e6fd5c9..5fee3dd 100644
--- a/src/engine/SCons/EnvironmentTests.py
+++ b/src/engine/SCons/EnvironmentTests.py
@@ -1162,7 +1162,9 @@ class EnvironmentTestCase(unittest.TestCase):
             exc_caught = 1
         assert exc_caught, "did not catch expected UserError"
 
-        env.Tool('cc')
+        # Use a non-existent toolpath directory just to make sure we
+        # can call Tool() with the keyword argument.
+        env.Tool('cc', toolpath=['/no/such/directory'])
         assert env['CC'] == 'cc', env['CC']
 
         env.Tool('$LINK')
diff --git a/src/engine/SCons/Tool/__init__.py b/src/engine/SCons/Tool/__init__.py
index a58ac6d..34e9e0d 100644
--- a/src/engine/SCons/Tool/__init__.py
+++ b/src/engine/SCons/Tool/__init__.py
@@ -55,9 +55,23 @@ class ToolSpec:
     def __str__(self):
         return self.name
     
-def Tool(name):
-    """Select a canned Tool specification.
-    """
+def Tool(name, toolpath=[]):
+    "Select a canned Tool specification, optionally searching in toolpath."
+
+    try:
+        file, path, desc = imp.find_module(name, toolpath)
+        try:
+            module = imp.load_module(name, file, path, desc)
+            spec = ToolSpec(name)
+            spec.generate = module.generate
+            spec.exists = module.exists
+            return spec
+        finally:
+            if file:
+                file.close()
+    except ImportError, e:
+        pass
+    
     full_name = 'SCons.Tool.' + name
     if not sys.modules.has_key(full_name):
         try: