git cl try: Simplify _get_bucket_map.

git_cl.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.
 
 # Copyright (C) 2008 Evan Martin <martine@danga.com>
 
 """A git-command for integrating reviews on Rietveld and Gerrit."""
 
 from __future__ import print_function
@@ skipping 323 matching lines @@
       raise httplib2.HttpLib2Error(content)
 
     # status >= 500 means transient failures.
     logging.debug('Transient errors when %s. Will retry.', operation_name)
     time_sleep(0.5 + 1.5*try_count)
     try_count += 1
   assert False, 'unreachable'
 
 
 def _get_bucket_map(changelist, options, option_parser):
-  """Returns a dict mapping bucket names (or master names) to
-  builders and tests, for triggering try jobs.
+  """Returns a dict mapping bucket names to builders and tests,
+  for triggering try jobs.
   """
+  # If no bots are listed, we try to get a set of builders and tests based
+  # on GetPreferredTryMasters functions in PRESUBMIT.py files.
   if not options.bot:
     change = changelist.GetChange(
         changelist.GetCommonAncestorWithUpstream(), None)
 
-    # Get try masters from PRESUBMIT.py files.
     masters = presubmit_support.DoGetTryMasters(
         change=change,
         changed_files=change.LocalPaths(),
         repository_root=settings.GetRoot(),
         default_presubmit=None,
         project=None,
         verbose=options.verbose,
         output_stream=sys.stdout)
 
     if masters:
       return masters
 
     # Fall back to deprecated method: get try slaves from PRESUBMIT.py
     # files.
     # TODO(qyearsley): Remove this.
     options.bot = presubmit_support.DoGetTrySlaves(
         change=change,
         changed_files=change.LocalPaths(),
         repository_root=settings.GetRoot(),
         default_presubmit=None,
         project=None,
         verbose=options.verbose,
         output_stream=sys.stdout)
 
     if not options.bot:
       return {}
 
+  # If a bucket or master is passed, then we assume all bots are under
+  # that one master.
   if options.bucket:
     return {options.bucket: {b: [] for b in options.bot}}
+  if options.master:
+    return {_prefix_master(options.master): {b: [] for b in options.bot}}
 
-  if not options.master:
-    bucket_map, error_message = _get_bucket_map_for_builders(options.bot)
-    if error_message:
-      option_parser.error(
-          'Tryserver master cannot be found because: %s\n'
-          'Please manually specify the tryserver master, e.g. '
-          '"-m tryserver.chromium.linux".' % error_message)
-    return bucket_map
-
-  builders_and_tests = {}
-
-  # TODO(machenbach): The old style command-line options don't support
-  # multiple try masters yet.
-  # TODO(qyearsley): If options.bot is always a list of strings, then
-  # "new_style" never applies, and so we should remove support for Specifying
-  # test filters completely.
-  old_style = filter(lambda x: isinstance(x, basestring), options.bot)
-  new_style = filter(lambda x: isinstance(x, tuple), options.bot)
-
-  for bot in old_style:
-    if ':' in bot:
-      option_parser.error('Specifying testfilter is no longer supported')
-    elif ',' in bot:
-      option_parser.error('Specify one bot per --bot flag')
-    else:
-      builders_and_tests.setdefault(bot, [])
-
-  for bot, tests in new_style:
-    builders_and_tests.setdefault(bot, []).extend(tests)
-
-  # Add the "master." prefix to the master name to obtain the bucket name.
-  bucket = _prefix_master(options.master)
-  return {bucket: builders_and_tests}
+  # If bots are listed but no master or bucket, then we need to find out
+  # the corresponding master for each bot.
+  bucket_map, error_message = _get_bucket_map_for_builders(options.bot)
+  if error_message:
+    option_parser.error(
+        'Tryserver master cannot be found because: %s\n'
+        'Please manually specify the tryserver master, e.g. '
+        '"-m tryserver.chromium.linux".' % error_message)
+  return bucket_map
 
 
 def _get_bucket_map_for_builders(builders):
   """Returns a map of buckets to builders for the given builders."""
   map_url = 'https://builders-map.appspot.com/'
   try:
     builders_map = json.load(urllib2.urlopen(map_url))
   except urllib2.URLError as e:
     return None, ('Failed to fetch builder-to-master map from %s. Error: %s.' %
                   (map_url, e))
   except ValueError as e:
     return None, ('Invalid json string from %s. Error: %s.' % (map_url, e))
   if not builders_map:
     return None, 'Failed to build master map.'
 
   bucket_map = {}
   for builder in builders:
-    builder = builder.split(':', 1)[0]
     masters = builders_map.get(builder, [])
     if not masters:
       return None, ('No matching master for builder %s.' % builder)
     if len(masters) > 1:
       return None, ('The builder name %s exists in multiple masters %s.' %
                     (builder, masters))
     bucket = _prefix_master(masters[0])
     bucket_map.setdefault(bucket, {})[builder] = []
 
   return bucket_map, None
@@ skipping 4420 matching lines @@
 
   error_message = cl.CannotTriggerTryJobReason()
   if error_message:
     parser.error('Can\'t trigger try jobs: %s' % error_message)
 
   if options.bucket and options.master:
     parser.error('Only one of --bucket and --master may be used.')
 
   buckets = _get_bucket_map(cl, options, parser)
 
+  # If no bots are listed and we couldn't get a list based on PRESUBMIT files,
+  # then we default to triggering a CQ dry run (see http://crbug.com/625697).
   if not buckets:
-    # Default to triggering Dry Run (see http://crbug.com/625697).
     if options.verbose:
       print('git cl try with no bots now defaults to CQ Dry Run.')
     return cl.TriggerDryRun()
 
   for builders in buckets.itervalues():
     if any('triggered' in b for b in builders):
       print('ERROR You are trying to send a job to a triggered bot. This type '
             'of bot requires an initial job from a parent (usually a builder). '
             'Instead send your job to the parent.\n'
             'Bot list: %s' % builders, file=sys.stderr)
@@ skipping 510 matching lines @@
 if __name__ == '__main__':
   # These affect sys.stdout so do it outside of main() to simplify mocks in
   # unit testing.
   fix_encoding.fix_encoding()
   setup_color.init()
   try:
     sys.exit(main(sys.argv[1:]))
   except KeyboardInterrupt:
     sys.stderr.write('interrupted\n')
     sys.exit(1)