cros_mark_as_stable: delete merge_branch if it already exists

cros_mark_as_stable.py

 #!/usr/bin/python
 
 # Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """This module uprevs a given package's ebuild to the next revision."""
 
 
 import fileinput
@@ skipping 92 matching lines @@
   for command in commands:
     command_usage += '  %s: %s\n' % (command, _COMMAND_DICTIONARY[command])
   commands_str = '|'.join(commands)
   print 'Usage: %s FLAGS [%s]\n\n%s\nFlags:%s' % (sys.argv[0], commands_str,
                                                   command_usage, gflags.FLAGS)
   if error_message:
     generate_test_report.Die(error_message)
   else:
     sys.exit(1)
 
+def _BranchExists(name):

[petkov, 2010/08/26 03:39:35]

Unused? Remove.

+  """Returns True is the branch exists"""
+  return _RunCommand('git branch').split().count(name) != 0
 
 def _PushChange():
   """Pushes changes to the git repository.
 
   Pushes locals commits from calls to CommitChange to the remote git
   repository specified by os.pwd.
 
   Raises:
       OSError: Error occurred while pushing.
   """
 
   # TODO(sosa) - Add logic for buildbot to check whether other slaves have
   # completed and push this change only if they have.
 
   # Sanity check to make sure we're on a stabilizing branch before pushing.
   if not _CheckOnStabilizingBranch():
     print 'Not on branch %s so no work found to push.  Exiting' % \
         _STABLE_BRANCH_NAME
     return
 
   description = _RunCommand('git log --format=format:%s%n%n%b ' +
                             gflags.FLAGS.tracking_branch + '..')
   description = 'Marking set of ebuilds as stable\n\n%s' % description
   merge_branch_name = 'merge_branch'
   _RunCommand('git remote update')
+  merge_branch = _GitBranch(merge_branch_name)
+  merge_branch.CreateBranch()
+  if not merge_branch.Exists():
+    generate_test_report.Die('Unable to create merge branch.')
   _RunCommand('git checkout -b %s %s' % (

[petkov, 2010/08/26 03:39:35]

This seems redundant with CreateBranch above. Does this reset the tracking
branch somehow? It seems cleaner to:

- Delete merge_branch if it Exists.
- Create a new merge branch (possibly by extending the CreateBranch method by
adding an optional tracking branch).

[petkov, 2010/08/26 16:47:18]

Btw, this does emit a "fatal" message:

...
HEAD is now at 120e432... Add support for using overlay-specific portage profile
directories to setup_board
Switched to a new branch 'merge_branch'
fatal: git checkout: branch merge_branch already exists
Counting objects: 8, done.
...

On 2010/08/26 03:39:35, petkov wrote:

       merge_branch_name, gflags.FLAGS.tracking_branch))
   _RunCommand('git merge --squash %s' % _STABLE_BRANCH_NAME)
   _RunCommand('git commit -m "%s"' % description)
   # Ugh. There has got to be an easier way to push to a tracking branch
   _RunCommand('git config push.default tracking')
   _RunCommand('git push')
 
 
 def _RunCommand(command):
   """Runs a shell command and returns stdout back to caller."""
@@ skipping 219 matching lines @@
              'and reset the git repo yourself.' %
              (package_list[:index], overlay_directory))
       raise e
   elif command == 'push':
     _PushChange()
 
 
 if __name__ == '__main__':
   main(sys.argv)