Add tag write access to merge script.

tools/push-to-trunk/git_recipes.py

 #!/usr/bin/env python
 # Copyright 2014 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
@@ skipping 83 matching lines @@
 
 
 class GitRecipesMixin(object):
   def GitIsWorkdirClean(self, **kwargs):
     return self.Git("status -s -uno", **kwargs).strip() == ""
 
   @Strip
   def GitBranch(self, **kwargs):
     return self.Git("branch", **kwargs)
 
+  @Strip
+  def GitRemoteContains(self, hsh, **kwargs):

[agable, 2014/09/29 09:49:12]

I'd be scared that someone might use this who doesn't fully understand it -- it
only looks at local remote-tracking branches, not actually at what is in the
remote server. So it's useless without a fetch first.

[Michael Achenbach, 2014/09/29 10:46:25]

I'll rename the function as it should be just used to determine the remote
branch's name, not for actually verifying a commit on a remote server.

+    """Returns the remote branch for a given commit.
+
+    Returns an empty string in case the commit doesn't exist on any remote

[agable, 2014/09/29 09:49:11]

None is a better sentinel value than "".

[Michael Achenbach, 2014/09/29 10:46:25]

Done. Was because of the @Strip wrapper. But I make that more robust.

+    branch.
+    Returns the last remote branch in case the commit exists on more than one.
+    """
+    branches = self.Git(MakeArgs(["branch -r --contains", hsh]),
+                        **kwargs).strip().splitlines()
+    return (branches or [""])[-1]
+
   def GitCreateBranch(self, name, branch="", **kwargs):
     assert name
     self.Git(MakeArgs(["checkout -b", name, branch]), **kwargs)
 
   def GitDeleteBranch(self, name, **kwargs):
     assert name
     self.Git(MakeArgs(["branch -D", name]), **kwargs)
 
   def GitReset(self, name, **kwargs):
     assert name
@@ skipping 191 matching lines @@
   def GitSVNFindSVNRev(self, git_hash, branch="", **kwargs):
     return self.Git(MakeArgs(["svn find-rev", git_hash, branch]), **kwargs)
 
   def GitSVNDCommit(self, **kwargs):
     return self.Git("svn dcommit 2>&1", retry_on=lambda x: x is None, **kwargs)
 
   def GitSVNTag(self, version, **kwargs):
     self.Git(("svn tag %s -m \"Tagging version %s\"" % (version, version)),
              retry_on=lambda x: x is None,
              **kwargs)