[Findit] Add a sub-pipeline to analyze failures caused by DEPS rolls.

appengine/findit/waterfall/build_failure_analysis.py

 # Copyright 2015 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import collections
 import os
 import re
 
 from common.diff import ChangeType
 from waterfall.failure_signal import FailureSignal
@@ skipping 258 matching lines @@
     for touched_file in change_log['touched_files']:
       _CheckFile(
           touched_file, file_path_in_log, justification, file_name_occurrences)
 
   if not justification.score:
     return None
   else:
     return justification.ToDict()
 
 
-def AnalyzeBuildFailure(failure_info, change_logs, failure_signals):
+# TODO: use DEPS info to detect dependency rolls -- pylint: disable=W0613
+def AnalyzeBuildFailure(
+    failure_info, change_logs, deps_info, failure_signals):
   """Analyze the given failure signals, and figure out culprit CLs.
 
   Args:
     failure_info (dict): Output of pipeline DetectFirstFailurePipeline.
     change_logs (dict): Output of pipeline PullChangelogPipeline.
+    deps_info (dict): Output of pipeline ExtractDEPSInfoPipeline.

[chanli, 2015/05/29 01:00:07]

Why I can't find where do you use this argument in the function?

[stgao, 2015/05/29 16:46:54]

I added a TODO above for that.

However, I made a change to use it to check for failures caused by DEPS roll.

     failure_signals (dict): Output of pipeline ExtractSignalPipeline.
 
   Returns:
     A dict with the following form:
     {
       'failures': [
         {
           'step_name': 'compile',
           'first_failure': 230,
           'last_pass': 229,
@@ skipping 19 matching lines @@
     }
   """
   analysis_result = {
       'failures': []
   }
 
   if not failure_info['failed']:
     return analysis_result
 
   def CreateCLInfoDict(justification_dict, build_number, change_log):
     # TODO(stgao): remove hard-coded 'chromium' when DEPS file parsing is

[chanli, 2015/05/29 01:00:07]

does this todo relate to thi CL?

[stgao, 2015/05/29 16:46:54]

More work is needed for this. I'd leave this as is for now.

     # supported.
     cl_info = {
         'build_number': build_number,
         'repo_name': 'chromium',
         'revision': change_log['revision'],
         'commit_position': change_log.get('commit_position'),
         'url':
             change_log.get('code_review_url') or change_log.get('commit_url'),
     }
 
@@ skipping 28 matching lines @@
         step_analysis_result['suspected_cls'].append(
             CreateCLInfoDict(justification_dict, build_number,
                              change_logs[revision]))
 
       build_number += 1
 
     # TODO(stgao): sort CLs by score.
     analysis_result['failures'].append(step_analysis_result)
 
   return analysis_result