Merged in manuelnaranjo/scons (pull request #159), added default for BUILDERS envvar

3 files changed, 11 insertions, 4 deletions

diff --git a/src/CHANGES.txt b/src/CHANGES.txt
index 17ee9751d..0ed523707 100644
--- a/src/CHANGES.txt
+++ b/src/CHANGES.txt
@@ -6,6 +6,10 @@
 
 RELEASE 2.3.2.alpha.yyyymmdd - NEW DATE WILL BE INSERTED HERE
 
+  From Manuel Francisco Naranjo:
+    - Added a default for the BUILDERS environment variable,
+      to prevent not defined exception on a Clone().
+
   From Andrew Featherstone:
     - Added description of CheckTypeSize method (#1991).
 
diff --git a/src/engine/SCons/Environment.py b/src/engine/SCons/Environment.py
index d178f4902..77898551b 100644
--- a/src/engine/SCons/Environment.py
+++ b/src/engine/SCons/Environment.py
@@ -1378,10 +1378,8 @@ class Base(SubstitutionEnvironment):
         (like a function).  There are no references to any mutable
         objects in the original Environment.
         """
-        try:
-            builders = self._dict['BUILDERS']
-        except KeyError:
-            pass
+
+        builders = self._dict.get('BUILDERS', {})
 
         clone = copy.copy(self)
         # BUILDERS is not safe to do a simple copy
diff --git a/src/engine/SCons/EnvironmentTests.py b/src/engine/SCons/EnvironmentTests.py
index 523534289..b9ef3f2cb 100644
--- a/src/engine/SCons/EnvironmentTests.py
+++ b/src/engine/SCons/EnvironmentTests.py
@@ -1892,6 +1892,11 @@ def generate(env):
         env = env.Clone(KEY_THAT_I_WANT=6, tools=[my_tool])
         assert env['KEY_THAT_I_WANT'] == real_value[0], env['KEY_THAT_I_WANT']
 
+        # test for pull request #150
+        env = self.TestEnvironment()
+        env._dict.pop('BUILDERS')
+        assert env.has_key('BUILDERS') is False
+        env2 = env.Clone()
 
     def test_Copy(self):
         """Test copying using the old env.Copy() method"""