Add --gtest_filter support to run_test_cases.py.

tools/isolate/run_test_cases.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.
 
 """Runs each test cases as a single shard, single process execution.
 
 Similar to sharding_supervisor.py but finer grained. Runs multiple instances in
 parallel.
 """
@@ skipping 539 matching lines @@
   print 'Flaky:   %4d %5.2f%%' % (len(flaky), len(flaky) * 100. / total)
   print 'Fail:    %4d %5.2f%%' % (len(fail), len(fail) * 100. / total)
   print '%.1fs Done running %d tests with %d executions. %.1f test/s' % (
       duration,
       len(results),
       nb_runs,
       nb_runs / duration)
   return int(bool(fail))
 
 
-def main():
+def main(argv):
   """CLI frontend to validate arguments."""
   def as_digit(variable, default):
     if variable.isdigit():
       return int(variable)
     return default
 
   parser = optparse.OptionParser(usage='%prog <options> [gtest]')
   parser.add_option(
       '-j', '--jobs',
       type='int',
@@ skipping 33 matching lines @@
       default=as_digit(os.environ.get('GTEST_SHARD_INDEX', ''), None),
       help='Shard index to run')
   group.add_option(
       '-s', '--shards',
       type='int',
       default=as_digit(os.environ.get('GTEST_TOTAL_SHARDS', ''), None),
       help='Total number of shards to calculate from the --index to run')
   group.add_option(
       '-T', '--test-case-file',
       help='File containing the exact list of test cases to run')
+  group.add_option(
+      '--gtest_filter',
+      help='Runs a single test, provideded to keep compatibility with '
+           'other tools')
   parser.add_option_group(group)
-  options, args = parser.parse_args()
+  options, args = parser.parse_args(argv)
 
   levels = [logging.ERROR, logging.INFO, logging.DEBUG]
   logging.basicConfig(
       level=levels[min(len(levels)-1, options.verbose)],
       format='%(levelname)5s %(module)15s(%(lineno)3d): %(message)s')
 
   if len(args) != 1:
     parser.error(
         'Please provide the executable line to run, if you need fancy things '
         'like xvfb, start this script from *inside* xvfb, it\'ll be much faster'
         '.')
 
   executable = args[0]
   if not os.path.isabs(executable):
     executable = os.path.abspath(executable)
   if sys.platform in ('cygwin', 'win32'):
     if not os.path.splitext(executable)[1]:
       executable += '.exe'
   if not os.path.isfile(executable):
     parser.error('"%s" doesn\'t exist.' % executable)
 
+  if options.gtest_filter:
+    # Override any other option.
+    # Based on UnitTestOptions::FilterMatchesTest() in
+    # http://code.google.com/p/googletest/source/browse/#svn%2Ftrunk%2Fsrc
+    if '-' in options.gtest_filter:
+      options.whitelist, options.blacklist = options.gtest_filter.split('-', 1)
+    else:
+      options.whitelist = options.gtest_filter
+      options.blacklist = ''
+    options.whitelist = [i for i in options.whitelist.split(':') if i]
+    options.blacklist = [i for i in options.blacklist.split(':') if i]
+
   # Grab the test cases.
   if options.test_case_file:
     with open(options.test_case_file, 'r') as f:
       test_cases = filter(None, f.read().splitlines())
   else:
     test_cases = get_test_cases(
         executable,
         options.whitelist,
         options.blacklist,
         options.index,
         options.shards)
 
   if not test_cases:
-    return
+    return 0
 
   return run_test_cases(
       executable,
       test_cases,
       options.jobs,
       options.timeout,
       options.no_dump)
 
 
 if __name__ == '__main__':
-  sys.exit(main())
+  sys.exit(main(sys.argv[1:]))