Check the canary builds up to the last-rolled WebKit revision.

The script now examines the DEPS file to know the WebKit revision.
This patch solves the last half of BUG 78538.

TEST=run canary-webkit-revisions.py and observe.
BUG=78538

Review URL: http://codereview.chromium.org/6993006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@85246 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 70 insertions, 15 deletions

diff --git a/webkit/tools/layout_tests/canary-webkit-revisions.py b/webkit/tools/layout_tests/canary-webkit-revisions.py
index cd7dd39..577fce9 100755
--- a/webkit/tools/layout_tests/canary-webkit-revisions.py
+++ b/webkit/tools/layout_tests/canary-webkit-revisions.py
@@ -15,10 +15,12 @@ are retrieved and printed.
 
 import json
 import optparse
+import re
 import sys
 import urllib2
 
-
+_WEBKIT_REVISION_IN_DEPS_RE = re.compile(r'"webkit_revision"\s*:\s*"(\d+)"')
+_DEPS_FILE_URL = "http://src.chromium.org/viewvc/chrome/trunk/src/DEPS"
 _DEFAULT_BUILDERS = [
   "Webkit Win",
   "Webkit Vista",
@@ -41,6 +43,39 @@ _TEST_SUFFIX = '">'
 _WEBKIT_TESTS = "webkit_tests"
 
 
+def _OpenUrl(url):
+  """Opens a URL.
+
+  Returns:
+      A file-like object in case of success, an empty list otherwise.
+  """
+  try:
+    return urllib2.urlopen(url)
+  except urllib2.URLError, url_error:
+    message = ""
+    # Surprisingly, urllib2.URLError has different attributes based on the
+    # kinds of errors -- "code" for HTTP-level errors, "reason" for others.
+    if hasattr(url_error, "code"):
+      message = "Status code: %d" % url_error.code
+    if hasattr(url_error, "reason"):
+      message = url_error.reason
+    print >>sys.stderr, "Failed to open %s: %s" % (url, message)
+  return []
+
+
+def _WebkitRevisionInDeps():
+  """Returns the WebKit revision specified in DEPS file.
+
+  Returns:
+      Revision number as int. -1 in case of error.
+  """
+  for line in _OpenUrl(_DEPS_FILE_URL):
+    match = _WEBKIT_REVISION_IN_DEPS_RE.search(line)
+    if match:
+      return int(match.group(1))
+  return -1
+
+
 class _BuildResult(object):
   """Build result for a builder.
 
@@ -59,8 +94,11 @@ class _BuildResult(object):
 
 def _BuilderUrlFor(builder, max_builds):
   """Constructs the URL for a builder to retrieve the last results."""
-  return ("http://build.chromium.org/p/chromium.webkit/json/builders/" +
-          urllib2.quote(builder) + "/builds?as_text=1&" +
+  url = ("http://build.chromium.org/p/chromium.webkit/json/builders/%s/builds" %
+         urllib2.quote(builder))
+  if max_builds == -1:
+    return url + "/_all?as_text=1"
+  return (url + "?as_text=1&" +
           '&'.join(["select=%d" % -i for i in range(1, 1 + max_builds)]))
 
 
@@ -75,7 +113,7 @@ def _ExtractFailingTests(build):
           return sorted(text[prefix + len(_TEST_PREFIX): suffix].split(","))
 
 
-def _RetrieveBuildResult(builder, max_builds):
+def _RetrieveBuildResult(builder, max_builds, oldest_revision_to_check):
   """Retrieves build results for a builder.
 
   Checks the last passing revision, the last run revision, and failing tests
@@ -84,6 +122,7 @@ def _RetrieveBuildResult(builder, max_builds):
   Args:
       builder: Builder name.
       max_builds: Maximum number of builds to check.
+      oldest_revision_to_check: Oldest WebKit revision to check.
 
   Returns:
       _BuildResult instance.
@@ -91,7 +130,7 @@ def _RetrieveBuildResult(builder, max_builds):
   last_run_revision = 0
   failing_tests = []
   succeeded = False
-  builds_json = urllib2.urlopen(_BuilderUrlFor(builder, max_builds))
+  builds_json = _OpenUrl(_BuilderUrlFor(builder, max_builds))
   if not builds_json:
     return _BuildResult(builder, 0, 0, failing_tests)
   builds = [(int(value["number"]), value) for unused_key, value
@@ -115,6 +154,8 @@ def _RetrieveBuildResult(builder, max_builds):
       revision = int(build["sourceStamp"]["changes"][-1]["revision"])
     if revision and not last_run_revision:
       last_run_revision = revision
+    if revision and revision < oldest_revision_to_check:
+      break
     if not succeeded or not revision:
       continue
     return _BuildResult(builder, revision, last_run_revision, failing_tests)
@@ -128,19 +169,21 @@ def _PrintPassingRevisions(results):
       results: A list of build results.
   """
   print "**** Passing revisions *****"
-  minimum_revision = sys.maxint
-  maximum_revision = 0
+  min_passing_revision = sys.maxint
+  max_passing_revision = 0
   for result in results:
     if result.last_passing_revision:
-      minimum_revision = min(minimum_revision, result.last_passing_revision)
-      maximum_revision = max(maximum_revision, result.last_passing_revision)
+      min_passing_revision = min(min_passing_revision,
+                                 result.last_passing_revision)
+      max_passing_revision = max(max_passing_revision,
+                                 result.last_passing_revision)
       print 'The last passing run was at r%d on "%s"' % (
           result.last_passing_revision, result.builder)
     else:
       print 'No passing runs on "%s"' % result.builder
-  if maximum_revision:
+  if max_passing_revision:
     print "Passing revision range: r%d - r%d" % (
-          minimum_revision, maximum_revision)
+          min_passing_revision, max_passing_revision)
 
 
 def _PrintFailingRevisions(results):
@@ -163,8 +206,13 @@ def _ParseOptions():
   """Parses command-line options."""
   parser = optparse.OptionParser(usage="%prog [options] [builders]")
   parser.add_option("-m", "--max_builds", type="int",
-                    default=_DEFAULT_MAX_BUILDS,
-                    help="maximum number of builds to check for each builder")
+                    default=-1,
+                    help="Maximum number of builds to check for each builder."
+                         " Defaults to all builds for which record is"
+                         " available. Checking is ended either when the maximum"
+                         " number is reached, the remaining builds are older"
+                         " than the DEPS WebKit revision, or a passing"
+                         " revision is found.")
   return parser.parse_args()
 
 
@@ -173,13 +221,20 @@ def _Main():
   options, builders = _ParseOptions()
   if not builders:
     builders = _DEFAULT_BUILDERS
-  print "Checking the last %d builds for:" % options.max_builds
+  oldest_revision_to_check = _WebkitRevisionInDeps()
+  if options.max_builds == -1 and oldest_revision_to_check == -1:
+    options.max_builds = _DEFAULT_MAX_BUILDS
+  if options.max_builds != -1:
+    print "Maxium number of builds to check: %d" % options.max_builds
+  if oldest_revision_to_check != -1:
+    print "Oldest revision to check: %d" % oldest_revision_to_check
   sys.stdout.flush()
   results = []
   for builder in builders:
     print '"%s"' % builder
     sys.stdout.flush()
-    results.append(_RetrieveBuildResult(builder, options.max_builds))
+    results.append(_RetrieveBuildResult(
+        builder, options.max_builds, oldest_revision_to_check))
   _PrintFailingRevisions(results)
   _PrintPassingRevisions(results)