Use context manager to manage OS environment in tests

test/cxxflags/gyptest-cxxflags.py

Index: test/cxxflags/gyptest-cxxflags.py
diff --git a/test/cxxflags/gyptest-cxxflags.py b/test/cxxflags/gyptest-cxxflags.py
index 70142e7cedadcac595b239e1b889c4aa3865a20b..e0daea2126a9aa1d52546bef69d435ac6b318029 100755
--- a/test/cxxflags/gyptest-cxxflags.py
+++ b/test/cxxflags/gyptest-cxxflags.py
@@ -12,29 +12,15 @@ the use of the environment during regeneration when the gyp file changes.
 import os
 import TestGyp
 
-env_stack = []
-
-
-def PushEnv():
-  env_copy = os.environ.copy()
-  env_stack.append(env_copy)
-
-def PopEnv():
-  os.eniron=env_stack.pop()

[Nils Barth (inactive), 2014/04/08 08:56:32]

Ow, notice the typos?
os.eniron (not os.en*v*iron)
Also shouldn't set os.environ: should clear()/update()

 
 # Regenerating build files when a gyp file changes is currently only supported
 # by the make generator.
 test = TestGyp.TestGyp(formats=['make'])
 
-try:
-  PushEnv()
-  os.environ['CXXFLAGS'] = '-O0'
+# We reset the environ after calling gyp. When the auto-regeneration happens,
+# the same define should be reused anyway.
+with TestGyp.LocalEnv({'CXXFLAGS': '-O0'}):
   test.run_gyp('cxxflags.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()
 
 test.build('cxxflags.gyp')
 
@@ -45,15 +31,8 @@ test.run_built_executable('cxxflags', stdout=expect)
 
 test.sleep()
 
-try:
-  PushEnv()
-  os.environ['CXXFLAGS'] = '-O2'
+with TestGyp.LocalEnv({'CXXFLAGS': '-O2'}):
   test.run_gyp('cxxflags.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()
 
 test.build('cxxflags.gyp')