Fix for single line file modification

tests/patch_test.py

 #!/usr/bin/env python
 # Copyright (c) 2012 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 patch.py."""
 
 import logging
 import os
 import posixpath
@@ skipping 53 matching lines @@
     self._check_patch(p, 'foo', 'data', is_binary=True)
 
   def testFilePatchBinaryNew(self):
     p = patch.FilePatchBinary('foo', 'data', [], is_new=True)
     self._check_patch(p, 'foo', 'data', is_binary=True, is_new=True)
 
   def testFilePatchDiff(self):
     p = patch.FilePatchDiff('chrome/file.cc', RAW.PATCH, [])
     self._check_patch(p, 'chrome/file.cc', RAW.PATCH, nb_hunks=1)
 
+  def testDifferent(self):
+    name = 'master/unittests/data/processes-summary.dat'
+    p = patch.FilePatchDiff(name, RAW.DIFFERENT, [])
+    self._check_patch(p, name, RAW.DIFFERENT, nb_hunks=1)
+
   def testFilePatchDiffHeaderMode(self):
     p = patch.FilePatchDiff('git_cl/git-cl', GIT.MODE_EXE, [])
     self._check_patch(
         p, 'git_cl/git-cl', GIT.MODE_EXE, is_git_diff=True, patchlevel=1,
         svn_properties=[('svn:executable', '*')], nb_hunks=0)
 
   def testFilePatchDiffHeaderModeIndex(self):
     p = patch.FilePatchDiff('git_cl/git-cl', GIT.MODE_EXE_JUNK, [])
     self._check_patch(
         p, 'git_cl/git-cl', GIT.MODE_EXE_JUNK, is_git_diff=True, patchlevel=1,
@@ skipping 409 matching lines @@
       self.fail()
     except patch.UnsupportedPatchFormat:
       pass
 
 
 if __name__ == '__main__':
   logging.basicConfig(level=
       [logging.WARNING, logging.INFO, logging.DEBUG][
         min(2, sys.argv.count('-v'))])
   unittest.main()