git map-branches: add --show-subject

git_map_branches.py

 #!/usr/bin/env python
 # Copyright 2014 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.
 
 """Provides a short mapping of all the branches in your local repo, organized
 by their upstream ('tracking branch') layout.
 
 Example:
 origin/master
@@ skipping 17 matching lines @@
 import argparse
 import collections
 import sys
 import subprocess2
 
 from third_party import colorama
 from third_party.colorama import Fore, Style
 
 from git_common import current_branch, upstream, tags, get_branches_info
 from git_common import get_git_version, MIN_UPSTREAM_TRACK_GIT_VERSION, hash_one
+from git_common import run
 
 DEFAULT_SEPARATOR = ' ' * 4
 
 
 class OutputManager(object):
   """Manages a number of OutputLines and formats them into aligned columns."""
 
   def __init__(self):
     self.lines = []
     self.nocolor = False
@@ skipping 55 matching lines @@
   """A class which constructs output representing the tree's branch structure.
 
   Attributes:
     __branches_info: a map of branches to their BranchesInfo objects which
       consist of the branch hash, upstream and ahead/behind status.
     __gone_branches: a set of upstreams which are not fetchable by git"""
 
   def __init__(self):
     self.verbosity = 0
     self.maxjobs = 0
+    self.show_subject = False
     self.output = OutputManager()
     self.__gone_branches = set()
     self.__branches_info = None
     self.__parent_map = collections.defaultdict(list)
     self.__current_branch = None
     self.__current_hash = None
     self.__tag_set = None
     self.__status_info = {}
 
   def start(self):
@@ skipping 128 matching lines @@
       line.append(center_separator, separator=' ')
       line.append(behind_string, separator=' ', color=Fore.MAGENTA)
       line.append(back_separator)
 
     # The Rietveld issue associated with the branch.
     if self.verbosity >= 2:
       none_text = '' if self.__is_invalid_parent(branch) else 'None'
       (url, color) = self.__status_info[branch]
       line.append(url or none_text, color=color)
 
+    # The subject of the most recent commit on the branch.
+    if self.show_subject:
+      line.append(run('log', '-n1', '--format=%s', branch))
+
     self.output.append(line)
 
     for child in sorted(self.__parent_map.pop(branch, ())):
       self.__append_branch(child, depth=depth + 1)
 
 
 def main(argv):
   colorama.init()
   if get_git_version() < MIN_UPSTREAM_TRACK_GIT_VERSION:
     print >> sys.stderr, (
         'This tool will not show all tracking information for git version '
         'earlier than ' +
         '.'.join(str(x) for x in MIN_UPSTREAM_TRACK_GIT_VERSION) +
         '. Please consider upgrading.')
 
   parser = argparse.ArgumentParser(
       description='Print a a tree of all branches parented by their upstreams')
   parser.add_argument('-v', action='count',
                       help='Display branch hash and Rietveld URL')
   parser.add_argument('--no-color', action='store_true', dest='nocolor',
                       help='Turn off colors.')
   parser.add_argument(
       '-j', '--maxjobs', action='store', type=int,
       help='The number of jobs to use when retrieving review status')
+  parser.add_argument('--show-subject', action='store_true',
+                      dest='show_subject', help='Show the commit subject.')
 
   opts = parser.parse_args(argv)
 
   mapper = BranchMapper()
   mapper.verbosity = opts.v
   mapper.output.nocolor = opts.nocolor
   mapper.maxjobs = opts.maxjobs
+  mapper.show_subject = opts.show_subject
   mapper.start()
   print mapper.output.as_formatted_string()
   return 0
 
 if __name__ == '__main__':
   try:
     sys.exit(main(sys.argv[1:]))
   except KeyboardInterrupt:
     sys.stderr.write('interrupted\n')
     sys.exit(1)