Prevent git from using any external diff program that may have been...

scm.py

 # 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.
 
 """SCM-specific utility classes."""
 
 import glob
 import os
 import re
 import shutil
@@ skipping 237 matching lines @@
 
   @staticmethod
   def GenerateDiff(cwd, branch=None, branch_head='HEAD', full_move=False,
                    files=None):
     """Diffs against the upstream branch or optionally another branch.
 
     full_move means that move or copy operations should completely recreate the
     files, usually in the prospect to apply the patch for a try job."""
     if not branch:
       branch = GIT.GetUpstreamBranch(cwd)
-    command = ['diff', '-p', '--no-prefix', branch + "..." + branch_head]
+    command = ['diff', '-p', '--no-prefix', '--no-ext-diff',
+               branch + "..." + branch_head]
     if not full_move:
       command.append('-C')
     # TODO(maruel): --binary support.
     if files:
       command.append('--')
       command.extend(files)
     diff = GIT.Capture(command, cwd)[0].splitlines(True)
     for i in range(len(diff)):
       # In the case of added files, replace /dev/null with the path to the
       # file being added.
@@ skipping 530 matching lines @@
     if not SVN.current_version:
       SVN.current_version = SVN.Capture(['--version']).split()[2]
     current_version_list = map(only_int, SVN.current_version.split('.'))
     for min_ver in map(int, min_version.split('.')):
       ver = current_version_list.pop(0)
       if ver < min_ver:
         return (False, SVN.current_version)
       elif ver > min_ver:
         return (True, SVN.current_version)
     return (True, SVN.current_version)