[Findit] Make sure two consecutive suspects are included in the same sub-range.

scripts/slave/recipes/findit/chromium/compile.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 json
 
 from recipe_engine.config import List
 from recipe_engine.config import Single
 from recipe_engine.recipe_api import Property
 
@@ skipping 150 matching lines @@
   #   sub-range1: r7 and [r8, r9, r10]
   #   sub-range2: r4 and [r5, r6]
   #   sub-range3: None and [r1, r2, r3]
   # Sub-ranges with newer revisions are tested first (sub-range1 -> sub-range2
   # -> sub-range3), because it is more likely that a newer revision is the
   # beginning of the compile breakage.
   suspected_revision_index = [
       all_revisions.index(r)
           for r in set(suspected_revisions) if r in all_revisions]
   if suspected_revision_index:
+    # For consecutive suspected revisions, make them all in the same sub-range
+    # by removing the newer revisions, but keep the oldest one.
+    suspected_revision_index = [i for i in suspected_revision_index
+                                if i - 1 not in suspected_revision_index]
+
     sub_ranges = []
     remaining_revisions = all_revisions[:]
     for index in sorted(suspected_revision_index, reverse=True):
       if index > 0:
         sub_ranges.append(remaining_revisions[index - 1:])
         remaining_revisions = remaining_revisions[:index - 1]
     # None is a placeholder for the last known good revision.
     sub_ranges.append([None] + remaining_revisions)
   else:
     # Treat the entire regression range as a single sub-range.
@@ skipping 264 matching lines @@
                              })) +
       api.override_step_data('test r4.check_targets',
                              api.json.output({
                                  'found': ['target_name'],
                                  'not_found': [],
                              })) +
       api.override_step_data('test r4.compile', retcode=1)
   )
 
   # Entire regression range: (r1, r6]
-  # Suspected_revisions: [r4]
+  # Suspected_revisions: [r4, r5]
   # Expected smaller ranges: [r3, [r4, r5, r6]], [None, [r2]]
   # Actual culprit: r3
   # Should only run compile on r3, and then r2.
   yield (
       api.test('find_culprit_at_first_revision_of_a_sub_range') +
       props(compile_targets=['target_name'],
             good_revision='r1',
             bad_revision='r6',
             suspected_revisions=['r4']) +
       api.override_step_data(
@@ skipping 64 matching lines @@
           'git commits in range',
           api.raw_io.stream_output(
               '\n'.join('r%d' % i for i in reversed(range(2, 6))))) +
       api.override_step_data('test r2.check_targets',
                              api.json.output({
                                  'found': ['target_name'],
                                  'not_found': [],
                              })) +
       api.override_step_data('test r2.compile', retcode=1)
   )