gclient_scm.py: Make working with git more reliable

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 47 matching lines @@
     c = [GIT.COMMAND]
     c.extend(args)
     try:
       return gclient_utils.CheckCall(c, in_directory, print_error)
     except gclient_utils.CheckCallError:
       if error_ok:
         return ('', '')
       raise
 
   @staticmethod
-  def CaptureStatus(files, upstream_branch='origin'):
+  def CaptureStatus(files, upstream_branch=None):
     """Returns git status.
 
     @files can be a string (one file) or a list of files.
 
     Returns an array of (status, file) tuples."""
+    if upstream_branch is None:
+      upstream_branch = GIT.GetUpstreamBranch(os.getcwd())
+      if upstream_branch is None:
+        raise Exception("Cannot determine upstream branch")
     command = ["diff", "--name-status", "-r", "%s..." % upstream_branch]
     if not files:
       pass
     elif isinstance(files, basestring):
       command.append(files)
     else:
       command.extend(files)
 
     status = GIT.Capture(command)[0].rstrip()
     results = []
@@ skipping 715 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)