Fix watchlists for windows, for files with backslash

tests/watchlists_unittest.py

 #!/usr/bin/python
 # Copyright (c) 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 watchlists.py."""
 
+import os
 import unittest
 import super_mox
 import watchlists
 
 
 class WatchlistsTest(super_mox.SuperMoxTestBase):
 
   def setUp(self):
     super_mox.SuperMoxTestBase.setUp(self)
     self.mox.StubOutWithMock(watchlists.Watchlists, '_HasWatchlistsFile')
@@ skipping 102 matching lines @@
           'views': %s,
         },
       } """ % (watchers, watchers)
     watchlists.Watchlists._HasWatchlistsFile().AndReturn(True)
     watchlists.Watchlists._ContentsOfWatchlistsFile().AndReturn(contents)
     self.mox.ReplayAll()
 
     wl = watchlists.Watchlists('/a/path')
     self.assertEqual(wl.GetWatchersForPaths(['file_views_mac']), watchers)
 
+  def testWinPathWatchers(self):
+    """Test watchers for a windows path (containing backward slashes)."""
+    watchers = ['abc@def.com', 'x1@xyz.org']
+    contents = \
+      """{
+        'WATCHLIST_DEFINITIONS': {
+          'browser': {
+            'filepath': 'chrome/browser/.*',
+          },
+        },
+        'WATCHLISTS': {
+          'browser': %s,
+        },
+      } """ % watchers
+    saved_sep = os.sep
+    os.sep = '\\'  # to pose as win32
+    watchlists.Watchlists._HasWatchlistsFile().AndReturn(True)
+    watchlists.Watchlists._ContentsOfWatchlistsFile().AndReturn(contents)
+    self.mox.ReplayAll()
+
+    wl = watchlists.Watchlists(r'a\path')
+    returned_watchers = wl.GetWatchersForPaths(
+          [r'chrome\browser\renderer_host\render_widget_host.h'])
+    os.sep = saved_sep  # revert back os.sep before asserts
+    self.assertEqual(returned_watchers, watchers)
+
 
 if __name__ == '__main__':
   unittest.main()