Let releases script retrieve information about chromium branches.

tools/push-to-trunk/releases.py

 #!/usr/bin/env python
 # Copyright 2014 the V8 project authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # This script retrieves the history of all V8 branches and trunk revisions and
 # their corresponding Chromium revisions.
 
+# Requires a chromium checkout with branch heads:
+# gclient sync --with_branch_heads
+# gclient fetch
+
 import argparse
 import csv
 import itertools
 import json
 import os
 import re
 import sys
 
 from common_includes import *
 
@@ skipping 61 matching lines @@
     result.append(release)
   return result
 
 
 def BuildRevisionRanges(cr_releases):
   """Returns a mapping of v8 revision -> chromium ranges.
   The ranges are comma-separated, each range has the form R1:R2. The newest
   entry is the only one of the form R1, as there is no end range.
 
   cr_releases is a list of [cr_rev, v8_rev] reverse-sorted by cr_rev.
+  cr_rev either refers to a chromium svn revision or a chromium branch number.
   """
   range_lists = {}
   cr_releases = FilterDuplicatesAndReverse(cr_releases)
 
   # Visit pairs of cr releases from oldest to newest.
   for cr_from, cr_to in itertools.izip(
       cr_releases, itertools.islice(cr_releases, 1, None)):
 
     # Assume the chromium revisions are all different.
     assert cr_from[0] != cr_to[0]
@@ skipping 67 matching lines @@
       # The branch name.
       "branch": branch,
       # The version for displaying in the form 3.26.3 or 3.26.3.12.
       "version": version,
       # The date of the commit.
       "date": self.GitLog(n=1, format="%ci", git_hash=git_hash),
       # Merged patches if available in the form 'r1234, r2345'.
       "patches_merged": patches,
       # Default for easier output formatting.
       "chromium_revision": "",
+      # Default for easier output formatting.
+      "chromium_branch": "",
       # Link to the CL on code review. Trunk pushes are not uploaded, so this
       # field will be populated below with the recent roll CL link.
       "review_link": MatchSafe(REVIEW_LINK_RE.search(body)),
       # Link to the commit message on google code.
       "revision_link": ("https://code.google.com/p/v8/source/detail?r=%s"
                         % revision),
     }, self["patch"]
 
   def GetReleasesFromBranch(self, branch):
     self.GitReset("svn/%s" % branch)
@@ skipping 132 matching lines @@
 
     # Clean up.
     self.GitCheckoutFileSafe(self._config[DEPS_FILE], "HEAD")
 
     # Add the chromium ranges to the v8 trunk releases.
     all_ranges = BuildRevisionRanges(cr_releases)
     trunk_dict = dict((r["revision"], r) for r in trunk_releases)
     for revision, ranges in all_ranges.iteritems():
       trunk_dict.get(revision, {})["chromium_revision"] = ranges
 
+
+# TODO(machenbach): Unify common code with method above.
+class RietrieveChromiumBranches(Step):
+  MESSAGE = "Retrieve Chromium branch information."
+  REQUIRES = "chrome_path"
+
+  def RunStep(self):
+    os.chdir(self["chrome_path"])
+
+    trunk_releases = filter(lambda r: r["branch"] == "trunk", self["releases"])
+    if not trunk_releases:  # pragma: no cover
+      print "No trunk releases detected. Skipping chromium history."
+      return True
+
+    oldest_v8_rev = int(trunk_releases[-1]["revision"])
+
+    # Filter out irrelevant branches.
+    branches = filter(lambda r: re.match(r"branch-heads/\d+", r),
+                      self.GitRemotes())
+
+    # Transform into pure branch numbers.
+    branches = map(lambda r: int(re.match(r"branch-heads/(\d+)", r).group(1)),
+                   branches)
+
+    branches = sorted(branches, reverse=True)
+
+    cr_branches = []
+    try:
+      for branch in branches:
+        if not self.GitCheckoutFileSafe(self._config[DEPS_FILE],
+                                        "branch-heads/%d" % branch):
+          break  # pragma: no cover
+        deps = FileToText(self.Config(DEPS_FILE))
+        match = DEPS_RE.search(deps)
+        if match:
+          v8_rev = match.group(1)
+          cr_branches.append([str(branch), v8_rev])
+
+          # Stop after reaching beyond the last v8 revision we want to update.
+          # We need a small buffer for possible revert/reland frenzies.
+          # TODO(machenbach): Subtraction is not git friendly.
+          if int(v8_rev) < oldest_v8_rev - 100:
+            break  # pragma: no cover
+
+    # Allow Ctrl-C interrupt.
+    except (KeyboardInterrupt, SystemExit):  # pragma: no cover
+      pass
+
+    # Clean up.
+    self.GitCheckoutFileSafe(self._config[DEPS_FILE], "HEAD")
+
+    # Add the chromium branches to the v8 trunk releases.
+    all_ranges = BuildRevisionRanges(cr_branches)
+    trunk_dict = dict((r["revision"], r) for r in trunk_releases)
+    for revision, ranges in all_ranges.iteritems():
+      trunk_dict.get(revision, {})["chromium_branch"] = ranges
+
+
 class SwitchV8(Step):
   MESSAGE = "Returning to V8 checkout."
   REQUIRES = "chrome_path"
 
   def RunStep(self):
     self.GitCheckout("master")
     self.GitDeleteBranch(self.Config(BRANCHNAME))
     os.chdir(self["v8_path"])
 
 
@@ skipping 42 matching lines @@
     return True
 
   def _Steps(self):
     return [
       Preparation,
       RetrieveV8Releases,
       CheckChromium,
       SwitchChromium,
       UpdateChromiumCheckout,
       RetrieveChromiumV8Releases,
+      RietrieveChromiumBranches,
       SwitchV8,
       CleanUp,
       WriteOutput,
     ]
 
 
 if __name__ == "__main__":  # pragma: no cover
   sys.exit(Releases(CONFIG).Run())