Push roll candidates based on candidate ref instead of lkgr.

tools/push-to-trunk/test_scripts.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 923 matching lines @@
 
   def testCheckLastPushRecently(self):
     self.Expect([
       Cmd(("git log -1 --format=%H --grep="
            "\"^Version [[:digit:]]*\.[[:digit:]]*\.[[:digit:]]* (based\" "
            "origin/candidates"), "hash2\n"),
       Cmd("git log -1 --format=%s hash2",
           "Version 3.4.5 (based on abc123)\n"),
     ])
 
-    self._state["lkgr"] = "abc123"
+    self._state["candidate"] = "abc123"
     self.assertEquals(0, self.RunStep(
         auto_push.AutoPush, CheckLastPush, AUTO_PUSH_ARGS))
 
   def testAutoPush(self):
     TextToFile("", os.path.join(TEST_CONFIG["DEFAULT_CWD"], ".git"))
     TEST_CONFIG["SETTINGS_LOCATION"] = "~/.doesnotexist"
 
     self.Expect([
       Cmd("git status -s -uno", ""),
       Cmd("git status -s -b -uno", "## some_branch\n"),
       Cmd("git fetch", ""),
       URL("https://v8-status.appspot.com/current?format=json",
           "{\"message\": \"Tree is throttled\"}"),
-      URL("https://v8-status.appspot.com/lkgr", Exception("Network problem")),
-      URL("https://v8-status.appspot.com/lkgr", "abc123"),
+      Cmd("git fetch origin +refs/heads/candidate:refs/heads/candidate", ""),
+      Cmd("git show-ref -s refs/heads/candidate", "abc123"),
       Cmd(("git log -1 --format=%H --grep=\""
            "^Version [[:digit:]]*\.[[:digit:]]*\.[[:digit:]]* (based\""
            " origin/candidates"), "push_hash\n"),
       Cmd("git log -1 --format=%s push_hash",
           "Version 3.4.5 (based on abc101)\n"),
     ])
 
     auto_push.AutoPush(TEST_CONFIG, self).Run(AUTO_PUSH_ARGS + ["--push"])
 
     state = json.loads(FileToText("%s-state.json"
                                   % TEST_CONFIG["PERSISTFILE_BASENAME"]))
 
-    self.assertEquals("abc123", state["lkgr"])
+    self.assertEquals("abc123", state["candidate"])
 
   def testAutoPushStoppedBySettings(self):
     TextToFile("", os.path.join(TEST_CONFIG["DEFAULT_CWD"], ".git"))
     TEST_CONFIG["SETTINGS_LOCATION"] = self.MakeEmptyTempFile()
     TextToFile("{\"enable_auto_push\": false}",
                TEST_CONFIG["SETTINGS_LOCATION"])
 
     self.Expect([
       Cmd("git status -s -uno", ""),
       Cmd("git status -s -b -uno", "## some_branch\n"),
@@ skipping 522 matching lines @@
 
 Review URL: https://codereview.chromium.org/83173002
 
 ------------------------------------------------------------------------""")
     self.assertEquals(
 """Prepare push to trunk.  Now working on version 3.23.11.
 
 R=danno@chromium.org
 
 Committed: https://code.google.com/p/v8/source/detail?r=17997""", body)