Abort `git cl push` if pushing into a local branch.

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."""
 
 from distutils.version import LooseVersion
@@ skipping 1726 matching lines @@
   # When submodules are added to the repo, we expect there to be a single
   # non-git-svn merge commit at remote HEAD with a signature comment.
   pattern = '^SVN changes up to revision [0-9]*$'
   cmd = ['rev-list', '--merges', '--grep=%s' % pattern, '%s^!' % ref]
   return RunGit(cmd) != ''
 
 
 def SendUpstream(parser, args, cmd):
   """Common code for CmdPush and CmdDCommit
 
-  Squashed commit into a single.
+  Squashes branch into a single commit.
   Updates changelog with metadata (e.g. pointer to review).
   Pushes/dcommits the code upstream.
   Updates review and closes.
   """
   parser.add_option('--bypass-hooks', action='store_true', dest='bypass_hooks',
                     help='bypass upload presubmit hook')
   parser.add_option('-m', dest='message',
                     help="override review description")
   parser.add_option('-f', action='store_true', dest='force',
                     help="force yes to questions (don't prompt)")
   parser.add_option('-c', dest='contributor',
                     help="external contributor for patch (appended to " +
                          "description and used as author for git). Should be " +
                          "formatted as 'First Last <email@example.com>'")
   add_git_similarity(parser)
   (options, args) = parser.parse_args(args)
   cl = Changelist()
 
+  current = cl.GetBranch()
+  remote, upstream_branch = cl.FetchUpstreamTuple(cl.GetBranch())
+  if not settings.GetIsGitSvn() and remote == '.':
+    print
+    print 'Attempting to push branch %r into another local branch!' % current
+    print
+    print 'Either reparent this branch on top of origin/master:'
+    print '  git reparent-branch --root'
+    print
+    print 'OR run `git rebase-update` if you think the parent branch is already'
+    print 'committed.'
+    print
+    print '  Current parent: %r' % upstream_branch
+    return 1
+
   if not args or cmd == 'push':
     # Default to merging against our best guess of the upstream branch.
     args = [cl.GetUpstreamBranch()]
 
   if options.contributor:
     if not re.match('^.*\s<\S+@\S+>$', options.contributor):
       print "Please provide contibutor as 'First Last <email@example.com>'"
       return 1
 
   base_branch = args[0]
@@ skipping 766 matching lines @@
         ('AppEngine is misbehaving and returned HTTP %d, again. Keep faith '
           'and retry or visit go/isgaeup.\n%s') % (e.code, str(e)))
 
 
 if __name__ == '__main__':
   # These affect sys.stdout so do it outside of main() to simplify mocks in
   # unit testing.
   fix_encoding.fix_encoding()
   colorama.init()
   sys.exit(main(sys.argv[1:]))