Retrieve bleeding edge push revision from trunk commit message.

tools/push-to-trunk/auto_roll.py

 #!/usr/bin/env python
 # Copyright 2013 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 86 matching lines @@
     match = re.match(r"^r(\d+) ", log)
     if not match:
       self.Die("Could not extract current svn revision from log.")
     self["latest"] = match.group(1)
 
 
 class CheckLastPush(Step):
   MESSAGE = "Checking last V8 push to trunk."
 
   def RunStep(self):
-    log = self.Git("svn log -1 --oneline ChangeLog").strip()
-    match = re.match(r"^r(\d+) \| Prepare push to trunk", log)
-    if match:
-      latest = int(self["latest"])
-      last_push = int(match.group(1))
-      # TODO(machebach): This metric counts all revisions. It could be
-      # improved by counting only the revisions on bleeding_edge.
-      if latest - last_push < 10:
-        # This makes sure the script doesn't push twice in a row when the cron
-        # job retries several times.
-        self.Die("Last push too recently: %d" % last_push)
+    last_push_hash = self.FindLastTrunkPush()
+    last_push = int(self.Git("svn find-rev %s" % last_push_hash).strip())
+
+    # TODO(machenbach): This metric counts all revisions. It could be
+    # improved by counting only the revisions on bleeding_edge.
+    if int(self["latest"]) - last_push < 10:
+      # This makes sure the script doesn't push twice in a row when the cron
+      # job retries several times.
+      self.Die("Last push too recently: %d" % last_push)
 
 
 class FetchLKGR(Step):
   MESSAGE = "Fetching V8 LKGR."
 
   def RunStep(self):
     lkgr_url = "https://v8-status.appspot.com/lkgr"
     # Retry several times since app engine might have issues.
     self["lkgr"] = self.ReadURL(lkgr_url, wait_plan=[5, 20, 300, 300])
 
@@ skipping 78 matching lines @@
   parser = BuildOptions()
   (options, args) = parser.parse_args()
   if not options.a or not options.c or not options.reviewer:
     print "You need to specify author, chromium src location and reviewer."
     parser.print_help()
     return 1
   RunAutoRoll(CONFIG, AutoRollOptions(options))
 
 if __name__ == "__main__":
   sys.exit(Main())