Disallow applying patches when git tree is dirty

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 2383 matching lines @@
                     help='failed patches spew .rej files rather than '
                         'attempting a 3-way merge')
   parser.add_option('-n', '--no-commit', action='store_true', dest='nocommit',
                     help="don't commit after patch applies")
   (options, args) = parser.parse_args(args)
   if len(args) != 1:
     parser.print_help()
     return 1
   issue_arg = args[0]
 
+  if is_dirty_git_tree('patch'):
+    return 1
+
   # TODO(maruel): Use apply_issue.py
   # TODO(ukai): use gerrit-cherry-pick for gerrit repository?
 
   if options.newbranch:
     if options.force:
       RunGit(['branch', '-D', options.newbranch],
           stderr=subprocess2.PIPE, error_ok=True)
     RunGit(['checkout', '-b', options.newbranch,
             Changelist().GetUpstreamBranch()])
 
@@ skipping 43 matching lines @@
   if directory:
     cmd.extend(('--directory', directory))
   if reject:
     cmd.append('--reject')
   elif IsGitVersionAtLeast('1.7.12'):
     cmd.append('--3way')
   try:
     subprocess2.check_call(cmd, env=GetNoGitPagerEnv(),
                            stdin=patch_data, stdout=subprocess2.VOID)
   except subprocess2.CalledProcessError:
+    RunGit(['reset', '--hard'])

[Sam Clegg, 2015/02/02 17:43:18]

I find this a little scary. Perhaps skip this and update the line below to be
"Failed to apply the patch (use git reset --hard to cleanup remnants)'.  I'm not
adamant about this I just have a fear of scripts that do "reset --hard" at any
point.  If you are sure this is not going to burn anyone I'm OK with leaving it
in as I think it is technically correct.

If you do choose to leave then in then perhaps assert(!is_dirty_git_tree) at
start of PatchIssue in case anyone else tries to call it later?

[wychen, 2015/02/03 02:33:44]

Done.

     DieWithError('Failed to apply the patch')
 
   # If we had an issue, commit the current state and register the issue.
   if not nocommit:
     RunGit(['commit', '-m', ('patch from issue %(i)s at patchset '
                              '%(p)s (http://crrev.com/%(i)s#ps%(p)s)'
                              % {'i': issue, 'p': patchset})])
     cl = Changelist()
     cl.SetIssue(issue)
     cl.SetPatchset(patchset)
@@ skipping 285 matching lines @@
     parser.error('Unrecognized args: %s' % ' '.join(args))
   cl = Changelist()
   # Ensure there actually is an issue to close.
   cl.GetDescription()
   cl.CloseIssue()
   return 0
 
 
 def CMDdiff(parser, args):
   """shows differences between local tree and last upload."""
+
+  # Uncommitted (staged and unstaged) changes will be destroyed by
+  # "git reset --hard" if there are merging conflicts in PatchIssue().
+  # Staged changes would be committed along with the patch from last
+  # upload, hence counted toward the "last upload" side in the final
+  # diff output, and this is not what we want.
+  if is_dirty_git_tree('diff'):
+    return 1
+
   cl = Changelist()
   issue = cl.GetIssue()
   branch = cl.GetBranch()
   if not issue:
     DieWithError('No issue found for current branch (%s)' % branch)
   TMP_BRANCH = 'git-cl-diff'
   base_branch = cl.GetCommonAncestorWithUpstream()
 
   # Create a new branch based on the merge-base
   RunGit(['checkout', '-q', '-b', TMP_BRANCH, base_branch])
@@ skipping 192 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:]))