Linux: make ninja respect environment:

test/cflags/gyptest-cflags.py

 #!/usr/bin/env python
 
 # Copyright (c) 2012 Google Inc. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """
 Verifies build of an executable with C++ define specified by a gyp define, and
 the use of the environment during regeneration when the gyp file changes.
 """
 
 import os
+import sys
 import TestGyp
 
 env_stack = []
 
 
 def PushEnv():
   env_copy = os.environ.copy()
   env_stack.append(env_copy)
 
 def PopEnv():
   os.eniron=env_stack.pop()
 
-# Regenerating build files when a gyp file changes is currently only supported
-# by the make generator.
-test = TestGyp.TestGyp(formats=['make'])
+formats = ['make']
+if sys.platform.startswith('linux'):
+  # Only Linux ninja generator supports CFLAGS.
+  formats.append('ninja')
+
+test = TestGyp.TestGyp(formats=formats)
 
 try:
   PushEnv()
   os.environ['CFLAGS'] = '-O0'
   test.run_gyp('cflags.gyp')
 finally:
   # We clear the environ after calling gyp.  When the auto-regeneration happens,
   # the same define should be reused anyway.  Reset to empty string first in
   # case the platform doesn't support unsetenv.
   PopEnv()
@@ skipping 18 matching lines @@
   PopEnv()
 
 test.build('cflags.gyp')
 
 expect = """\
 Using an optimization flag
 """
 test.run_built_executable('cflags', stdout=expect)
 
 test.pass_test()