Git support in presubmit tests....

tests/presubmit_unittest.py

 #!/usr/bin/python
 # Copyright (c) 2006-2009 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Unit tests for presubmit_support.py and presubmit_canned_checks.py."""
 
 import exceptions
 import os
 import StringIO
@@ skipping 35 matching lines @@
     self.mox.StubOutWithMock(presubmit, 'os')
     self.mox.StubOutWithMock(presubmit.os, 'path')
     presubmit.os.sep = os_sep
     presubmit.os.path.join = os_path_join
     presubmit.os.path.dirname = os_path_dirname
     presubmit.os.path.normpath = os_path_normpath
     presubmit.os.path.splitext = os_path_splitext
     self.mox.StubOutWithMock(presubmit, 'random')
     self.mox.StubOutWithMock(presubmit, 'sys')
     presubmit._ASKED_FOR_FEEDBACK = False
+    presubmit.os.path.commonprefix = os_path_commonprefix
+    self.fake_root_dir = self.RootDir()
     # Special mocks.
     def MockAbsPath(f):
       return f
+    def MockChdir(f):
+      return None
     presubmit.os.path.abspath = MockAbsPath
-    presubmit.os.path.commonprefix = os_path_commonprefix
-    self.fake_root_dir = self.RootDir()
+    presubmit.os.getcwd = self.RootDir
+    presubmit.os.chdir = MockChdir
     self.mox.StubOutWithMock(presubmit.gclient_scm, 'CaptureSVNInfo')
     self.mox.StubOutWithMock(presubmit.gcl, 'GetSVNFileProperty')
     self.mox.StubOutWithMock(presubmit.gcl, 'ReadFile')
 
 
 class PresubmitUnittest(PresubmitTestsBase):
   """General presubmit_support.py tests (excluding InputApi and OutputApi)."""
   def testMembersChanged(self):
     self.mox.ReplayAll()
     members = [
@@ skipping 1336 matching lines @@
     process.communicate().AndReturn(('', ''))
     self.mox.ReplayAll()
 
     results = presubmit_canned_checks.RunPythonUnitTests(
         input_api, presubmit.OutputApi, ['test_module'])
     self.assertEquals(len(results), 0)
 
 
 if __name__ == '__main__':
   unittest.main()