Gerrit git cl upload: implement patchset title (message).

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 distutils.version import LooseVersion
@@ skipping 2216 matching lines @@
     options.squash = ((settings.GetSquashGerritUploads() or options.squash) and
                       not options.no_squash)
     # We assume the remote called "origin" is the one we want.
     # It is probably not worthwhile to support different workflows.
     gerrit_remote = 'origin'
 
     remote, remote_branch = self.GetRemoteBranch()
     branch = GetTargetRef(remote, remote_branch, options.target_branch,
                           pending_prefix='')
 
-    if options.title:
-      # TODO(tandrii): it's now supported by Gerrit, implement!
-      print "\nPatch titles (-t) are not supported in Gerrit. Aborting..."
-      return 1
-
     if options.squash:
       if not self.GetIssue():
         # TODO(tandrii): deperecate this after 2016Q2.  Backwards compatibility
         # with shadow branch, which used to contain change-id for a given
         # branch, using which we can fetch actual issue number and set it as the
         # property of the branch, which is the new way.
         message = RunGitSilent([
             'show', '--format=%B', '-s',
             'refs/heads/git_cl_uploads/%s' % self.GetBranch()])
         if message:
@@ skipping 127 matching lines @@
             'to see which commits will be uploaded: ' % len(commits))
       print('git log %s..%s' % (parent, ref_to_push))
       print('You can also use `git squash-branch` to squash these into a '
             'single commit.')
       ask_for_data('About to upload; enter to confirm.')
 
     if options.reviewers or options.tbr_owners:
       change_desc.update_reviewers(options.reviewers, options.tbr_owners,
                                    change)
 
+    # Extra options that can be specified at push time. Doc:
+    # https://gerrit-review.googlesource.com/Documentation/user-upload.html
+    refspec_opts = []
+    if options.title:
+      # Per doc, spaces must be converted to underscores, and Gerrit will do the
+      # reverse on its side.
+      if '_' in options.title:
+        print('WARNING: underscores in title will be converted to spaces.')
+      refspec_opts.append('m=' + options.title.replace(' ', '_'))
+
     receive_options = []
     cc = self.GetCCList().split(',')
     if options.cc:
       cc.extend(options.cc)
     cc = filter(None, cc)
     if cc:
       receive_options += ['--cc=' + email for email in cc]
     if change_desc.get_reviewers():
       receive_options.extend(
           '--reviewer=' + email for email in change_desc.get_reviewers())
 
-    git_command = ['push']
+    git_command = ['git', 'push']
     if receive_options:
+      # TODO(tandrii): clean this up in follow up. This doesn't work, as it gets
+      # totally ignored by Gerrit.
       git_command.append('--receive-pack=git receive-pack %s' %
                          ' '.join(receive_options))
-    git_command += [gerrit_remote, ref_to_push + ':refs/for/' + branch]
+
+    refspec_suffix = ''
+    if refspec_opts:
+      refspec_suffix = '%' + ','.join(refspec_opts)
+      assert ' ' not in refspec_suffix, (
+          'spaces not allowed in refspec: "%s"' % refspec_suffix)
+
+    refspec = '%s:refs/for/%s%s' % (ref_to_push, branch, refspec_suffix)
+    git_command += [gerrit_remote, refspec]
+
     push_stdout = gclient_utils.CheckCallAndFilter(
-        ['git'] + git_command,
+        git_command,
         print_stdout=True,
         # Flush after every line: useful for seeing progress when running as
         # recipe.
         filter_fn=lambda _: sys.stdout.flush())
 
     if options.squash:
       regex = re.compile(r'remote:\s+https?://[\w\-\.\/]*/(\d+)\s.*')
       change_numbers = [m.group(1)
                         for m in map(regex.match, push_stdout.splitlines())
                         if m]
@@ skipping 2280 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)