Home | History | Annotate | Download | only in skia 
      1 # Copyright (c) 2013 The Chromium Authors. All rights reserved.
      2 # Use of this source code is governed by a BSD-style license that can be
      3 # found in the LICENSE file.
      4 
      5 
      6 """Top-level presubmit script for Skia.
      7 
      8 See http://dev.chromium.org/developers/how-tos/depottools/presubmit-scripts
      9 for more details about the presubmit API built into gcl.
     10 """
     11 
     12 import collections
     13 import csv
     14 import fnmatch
     15 import os
     16 import re
     17 import subprocess
     18 import sys
     19 import traceback
     20 
     21 
     22 REVERT_CL_SUBJECT_PREFIX = 'Revert '
     23 
     24 SKIA_TREE_STATUS_URL = 'http://skia-tree-status.appspot.com'
     25 
     26 # Please add the complete email address here (and not just 'xyz@' or 'xyz').
     27 PUBLIC_API_OWNERS = (
     28     'reed (at] chromium.org',
     29     'reed (at] google.com',
     30     'bsalomon (at] chromium.org',
     31     'bsalomon (at] google.com',
     32     'djsollen (at] chromium.org',
     33     'djsollen (at] google.com',
     34     'hcm (at] chromium.org',
     35     'hcm (at] google.com',
     36 )
     37 
     38 AUTHORS_FILE_NAME = 'AUTHORS'
     39 
     40 DOCS_PREVIEW_URL = 'https://skia.org/?cl='
     41 GOLD_TRYBOT_URL = 'https://gold.skia.org/search?issue='
     42 
     43 # Path to CQ bots feature is described in https://bug.skia.org/4364
     44 PATH_PREFIX_TO_EXTRA_TRYBOTS = {
     45     'src/opts/':
     46         'skia.primary:Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD',
     47     'include/private/SkAtomics.h': ('skia.primary:'
     48       'Test-Ubuntu-Clang-GCE-CPU-AVX2-x86_64-Release-TSAN,'
     49       'Test-Ubuntu-Clang-Golo-GPU-GT610-x86_64-Release-TSAN-Trybot'
     50     ),
     51 
     52     # Below are examples to show what is possible with this feature.
     53     # 'src/svg/': 'master1:abc;master2:def',
     54     # 'src/svg/parser/': 'master3:ghi,jkl;master4:mno',
     55     # 'src/image/SkImage_Base.h': 'master5:pqr,stu;master1:abc1;master2:def',
     56 }
     57 
     58 
     59 def _CheckChangeHasEol(input_api, output_api, source_file_filter=None):
     60   """Checks that files end with atleast one \n (LF)."""
     61   eof_files = []
     62   for f in input_api.AffectedSourceFiles(source_file_filter):
     63     contents = input_api.ReadFile(f, 'rb')
     64     # Check that the file ends in atleast one newline character.
     65     if len(contents) > 1 and contents[-1:] != '\n':
     66       eof_files.append(f.LocalPath())
     67 
     68   if eof_files:
     69     return [output_api.PresubmitPromptWarning(
     70       'These files should end in a newline character:',
     71       items=eof_files)]
     72   return []
     73 
     74 
     75 def _PythonChecks(input_api, output_api):
     76   """Run checks on any modified Python files."""
     77   pylint_disabled_warnings = (
     78       'F0401',  # Unable to import.
     79       'E0611',  # No name in module.
     80       'W0232',  # Class has no __init__ method.
     81       'E1002',  # Use of super on an old style class.
     82       'W0403',  # Relative import used.
     83       'R0201',  # Method could be a function.
     84       'E1003',  # Using class name in super.
     85       'W0613',  # Unused argument.
     86       'W0105',  # String statement has no effect.
     87   )
     88   # Run Pylint on only the modified python files. Unfortunately it still runs
     89   # Pylint on the whole file instead of just the modified lines.
     90   affected_python_files = []
     91   for affected_file in input_api.AffectedSourceFiles(None):
     92     affected_file_path = affected_file.LocalPath()
     93     if affected_file_path.endswith('.py'):
     94       affected_python_files.append(affected_file_path)
     95   return input_api.canned_checks.RunPylint(
     96       input_api, output_api,
     97       disabled_warnings=pylint_disabled_warnings,
     98       white_list=affected_python_files)
     99 
    100 
    101 def _IfDefChecks(input_api, output_api):
    102   """Ensures if/ifdef are not before includes. See skbug/3362 for details."""
    103   comment_block_start_pattern = re.compile('^\s*\/\*.*$')
    104   comment_block_middle_pattern = re.compile('^\s+\*.*')
    105   comment_block_end_pattern = re.compile('^\s+\*\/.*$')
    106   single_line_comment_pattern = re.compile('^\s*//.*$')
    107   def is_comment(line):
    108     return (comment_block_start_pattern.match(line) or
    109             comment_block_middle_pattern.match(line) or
    110             comment_block_end_pattern.match(line) or
    111             single_line_comment_pattern.match(line))
    112 
    113   empty_line_pattern = re.compile('^\s*$')
    114   def is_empty_line(line):
    115     return empty_line_pattern.match(line)
    116 
    117   failing_files = []
    118   for affected_file in input_api.AffectedSourceFiles(None):
    119     affected_file_path = affected_file.LocalPath()
    120     if affected_file_path.endswith('.cpp') or affected_file_path.endswith('.h'):
    121       f = open(affected_file_path)
    122       for line in f.xreadlines():
    123         if is_comment(line) or is_empty_line(line):
    124           continue
    125         # The below will be the first real line after comments and newlines.
    126         if line.startswith('#if 0 '):
    127           pass
    128         elif line.startswith('#if ') or line.startswith('#ifdef '):
    129           failing_files.append(affected_file_path)
    130         break
    131 
    132   results = []
    133   if failing_files:
    134     results.append(
    135         output_api.PresubmitError(
    136             'The following files have #if or #ifdef before includes:\n%s\n\n'
    137             'See https://bug.skia.org/3362 for why this should be fixed.' %
    138                 '\n'.join(failing_files)))
    139   return results
    140 
    141 
    142 def _CopyrightChecks(input_api, output_api, source_file_filter=None):
    143   results = []
    144   year_pattern = r'\d{4}'
    145   year_range_pattern = r'%s(-%s)?' % (year_pattern, year_pattern)
    146   years_pattern = r'%s(,%s)*,?' % (year_range_pattern, year_range_pattern)
    147   copyright_pattern = (
    148       r'Copyright (\([cC]\) )?%s \w+' % years_pattern)
    149 
    150   for affected_file in input_api.AffectedSourceFiles(source_file_filter):
    151     if 'third_party' in affected_file.LocalPath():
    152       continue
    153     contents = input_api.ReadFile(affected_file, 'rb')
    154     if not re.search(copyright_pattern, contents):
    155       results.append(output_api.PresubmitError(
    156           '%s is missing a correct copyright header.' % affected_file))
    157   return results
    158 
    159 
    160 def _ToolFlags(input_api, output_api):
    161   """Make sure `{dm,nanobench}_flags.py test` passes if modified."""
    162   results = []
    163   sources = lambda x: ('dm_flags.py'        in x.LocalPath() or
    164                        'nanobench_flags.py' in x.LocalPath())
    165   for f in input_api.AffectedSourceFiles(sources):
    166     if 0 != subprocess.call(['python', f.LocalPath(), 'test']):
    167       results.append(output_api.PresubmitError('`python %s test` failed' % f))
    168   return results
    169 
    170 
    171 def _InfraTests(input_api, output_api):
    172   """Run the infra tests."""
    173   results = []
    174   if not any(f.LocalPath().startswith('infra')
    175              for f in input_api.AffectedFiles()):
    176     return results
    177 
    178   cmd = ['python', os.path.join('infra', 'bots', 'infra_tests.py')]
    179   try:
    180     subprocess.check_output(cmd)
    181   except subprocess.CalledProcessError as e:
    182     results.append(output_api.PresubmitError(
    183         '`%s` failed:\n%s' % (' '.join(cmd), e.output)))
    184   return results
    185 
    186 
    187 def _CheckGNFormatted(input_api, output_api):
    188   """Make sure any .gn files we're changing have been formatted."""
    189   results = []
    190   for f in input_api.AffectedFiles():
    191     if (not f.LocalPath().endswith('.gn') and
    192         not f.LocalPath().endswith('.gni')):
    193       continue
    194 
    195     gn = 'gn.bat' if 'win32' in sys.platform else 'gn'
    196     cmd = [gn, 'format', '--dry-run', f.LocalPath()]
    197     try:
    198       subprocess.check_output(cmd)
    199     except subprocess.CalledProcessError:
    200       fix = 'gn format ' + f.LocalPath()
    201       results.append(output_api.PresubmitError(
    202           '`%s` failed, try\n\t%s' % (' '.join(cmd), fix)))
    203   return results
    204 
    205 
    206 def _CommonChecks(input_api, output_api):
    207   """Presubmit checks common to upload and commit."""
    208   results = []
    209   sources = lambda x: (x.LocalPath().endswith('.h') or
    210                        x.LocalPath().endswith('.py') or
    211                        x.LocalPath().endswith('.sh') or
    212                        x.LocalPath().endswith('.m') or
    213                        x.LocalPath().endswith('.mm') or
    214                        x.LocalPath().endswith('.go') or
    215                        x.LocalPath().endswith('.c') or
    216                        x.LocalPath().endswith('.cc') or
    217                        x.LocalPath().endswith('.cpp'))
    218   results.extend(
    219       _CheckChangeHasEol(
    220           input_api, output_api, source_file_filter=sources))
    221   results.extend(_PythonChecks(input_api, output_api))
    222   results.extend(_IfDefChecks(input_api, output_api))
    223   results.extend(_CopyrightChecks(input_api, output_api,
    224                                   source_file_filter=sources))
    225   results.extend(_ToolFlags(input_api, output_api))
    226   return results
    227 
    228 
    229 def CheckChangeOnUpload(input_api, output_api):
    230   """Presubmit checks for the change on upload.
    231 
    232   The following are the presubmit checks:
    233   * Check change has one and only one EOL.
    234   """
    235   results = []
    236   results.extend(_CommonChecks(input_api, output_api))
    237   # Run on upload, not commit, since the presubmit bot apparently doesn't have
    238   # coverage or Go installed.
    239   results.extend(_InfraTests(input_api, output_api))
    240 
    241   results.extend(_CheckGNFormatted(input_api, output_api))
    242   return results
    243 
    244 
    245 def _CheckTreeStatus(input_api, output_api, json_url):
    246   """Check whether to allow commit.
    247 
    248   Args:
    249     input_api: input related apis.
    250     output_api: output related apis.
    251     json_url: url to download json style status.
    252   """
    253   tree_status_results = input_api.canned_checks.CheckTreeIsOpen(
    254       input_api, output_api, json_url=json_url)
    255   if not tree_status_results:
    256     # Check for caution state only if tree is not closed.
    257     connection = input_api.urllib2.urlopen(json_url)
    258     status = input_api.json.loads(connection.read())
    259     connection.close()
    260     if ('caution' in status['message'].lower() and
    261         os.isatty(sys.stdout.fileno())):
    262       # Display a prompt only if we are in an interactive shell. Without this
    263       # check the commit queue behaves incorrectly because it considers
    264       # prompts to be failures.
    265       short_text = 'Tree state is: ' + status['general_state']
    266       long_text = status['message'] + '\n' + json_url
    267       tree_status_results.append(
    268           output_api.PresubmitPromptWarning(
    269               message=short_text, long_text=long_text))
    270   else:
    271     # Tree status is closed. Put in message about contacting sheriff.
    272     connection = input_api.urllib2.urlopen(
    273         SKIA_TREE_STATUS_URL + '/current-sheriff')
    274     sheriff_details = input_api.json.loads(connection.read())
    275     if sheriff_details:
    276       tree_status_results[0]._message += (
    277           '\n\nPlease contact the current Skia sheriff (%s) if you are trying '
    278           'to submit a build fix\nand do not know how to submit because the '
    279           'tree is closed') % sheriff_details['username']
    280   return tree_status_results
    281 
    282 
    283 class CodeReview(object):
    284   """Abstracts which codereview tool is used for the specified issue."""
    285 
    286   def __init__(self, input_api):
    287     self._issue = input_api.change.issue
    288     self._gerrit = input_api.gerrit
    289     self._rietveld_properties = None
    290     if not self._gerrit:
    291       self._rietveld_properties = input_api.rietveld.get_issue_properties(
    292           issue=int(self._issue), messages=True)
    293 
    294   def GetOwnerEmail(self):
    295     if self._gerrit:
    296       return self._gerrit.GetChangeOwner(self._issue)
    297     else:
    298       return self._rietveld_properties['owner_email']
    299 
    300   def GetSubject(self):
    301     if self._gerrit:
    302       return self._gerrit.GetChangeInfo(self._issue)['subject']
    303     else:
    304       return self._rietveld_properties['subject']
    305 
    306   def GetDescription(self):
    307     if self._gerrit:
    308       return self._gerrit.GetChangeDescription(self._issue)
    309     else:
    310       return self._rietveld_properties['description']
    311 
    312   def IsDryRun(self):
    313     if self._gerrit:
    314       return self._gerrit.GetChangeInfo(
    315           self._issue)['labels']['Commit-Queue'].get('value', 0) == 1
    316     else:
    317       return self._rietveld_properties['cq_dry_run']
    318 
    319   def GetReviewers(self):
    320     if self._gerrit:
    321       code_review_label = (
    322           self._gerrit.GetChangeInfo(self._issue)['labels']['Code-Review'])
    323       return [r['email'] for r in code_review_label.get('all', [])]
    324     else:
    325       return self._rietveld_properties['reviewers']
    326 
    327   def GetApprovers(self):
    328     approvers = []
    329     if self._gerrit:
    330       code_review_label = (
    331           self._gerrit.GetChangeInfo(self._issue)['labels']['Code-Review'])
    332       for m in code_review_label.get('all', []):
    333         if m.get("value") == 1:
    334           approvers.append(m["email"])
    335     else:
    336       for m in self._rietveld_properties.get('messages', []):
    337         if 'lgtm' in m['text'].lower():
    338           approvers.append(m['sender'])
    339     return approvers
    340 
    341 
    342 def _CheckOwnerIsInAuthorsFile(input_api, output_api):
    343   results = []
    344   if input_api.change.issue:
    345     cr = CodeReview(input_api)
    346 
    347     owner_email = cr.GetOwnerEmail()
    348     try:
    349       authors_content = ''
    350       for line in open(AUTHORS_FILE_NAME):
    351         if not line.startswith('#'):
    352           authors_content += line
    353       email_fnmatches = re.findall('<(.*)>', authors_content)
    354       for email_fnmatch in email_fnmatches:
    355         if fnmatch.fnmatch(owner_email, email_fnmatch):
    356           # Found a match, the user is in the AUTHORS file break out of the loop
    357           break
    358       else:
    359         results.append(
    360           output_api.PresubmitError(
    361             'The email %s is not in Skia\'s AUTHORS file.\n'
    362             'Issue owner, this CL must include an addition to the Skia AUTHORS '
    363             'file.'
    364             % owner_email))
    365     except IOError:
    366       # Do not fail if authors file cannot be found.
    367       traceback.print_exc()
    368       input_api.logging.error('AUTHORS file not found!')
    369 
    370   return results
    371 
    372 
    373 def _CheckLGTMsForPublicAPI(input_api, output_api):
    374   """Check LGTMs for public API changes.
    375 
    376   For public API files make sure there is an LGTM from the list of owners in
    377   PUBLIC_API_OWNERS.
    378   """
    379   results = []
    380   requires_owner_check = False
    381   for affected_file in input_api.AffectedFiles():
    382     affected_file_path = affected_file.LocalPath()
    383     file_path, file_ext = os.path.splitext(affected_file_path)
    384     # We only care about files that end in .h and are under the top-level
    385     # include dir, but not include/private.
    386     if (file_ext == '.h' and
    387         'include' == file_path.split(os.path.sep)[0] and
    388         'private' not in file_path):
    389       requires_owner_check = True
    390 
    391   if not requires_owner_check:
    392     return results
    393 
    394   lgtm_from_owner = False
    395   if input_api.change.issue:
    396     cr = CodeReview(input_api)
    397 
    398     if re.match(REVERT_CL_SUBJECT_PREFIX, cr.GetSubject(), re.I):
    399       # It is a revert CL, ignore the public api owners check.
    400       return results
    401 
    402     if cr.IsDryRun():
    403       # Ignore public api owners check for dry run CLs since they are not
    404       # going to be committed.
    405       return results
    406 
    407     if input_api.gerrit:
    408       for reviewer in cr.GetReviewers():
    409         if reviewer in PUBLIC_API_OWNERS:
    410           # If an owner is specified as an reviewer in Gerrit then ignore the
    411           # public api owners check.
    412           return results
    413     else:
    414       match = re.search(r'^TBR=(.*)$', cr.GetDescription(), re.M)
    415       if match:
    416         tbr_section = match.group(1).strip().split(' ')[0]
    417         tbr_entries = tbr_section.split(',')
    418         for owner in PUBLIC_API_OWNERS:
    419           if owner in tbr_entries or owner.split('@')[0] in tbr_entries:
    420             # If an owner is specified in the TBR= line then ignore the public
    421             # api owners check.
    422             return results
    423 
    424     if cr.GetOwnerEmail() in PUBLIC_API_OWNERS:
    425       # An owner created the CL that is an automatic LGTM.
    426       lgtm_from_owner = True
    427 
    428     for approver in cr.GetApprovers():
    429       if approver in PUBLIC_API_OWNERS:
    430         # Found an lgtm in a message from an owner.
    431         lgtm_from_owner = True
    432         break
    433 
    434   if not lgtm_from_owner:
    435     results.append(
    436         output_api.PresubmitError(
    437             "If this CL adds to or changes Skia's public API, you need an LGTM "
    438             "from any of %s.  If this CL only removes from or doesn't change "
    439             "Skia's public API, please add a short note to the CL saying so. "
    440             "Add one of the owners as a reviewer to your CL. For Rietveld CLs "
    441             "you also need to add one of those owners on a TBR= line.  If you "
    442             "don't know if this CL affects Skia's public API, treat it like it "
    443             "does." % str(PUBLIC_API_OWNERS)))
    444   return results
    445 
    446 
    447 def PostUploadHook(cl, change, output_api):
    448   """git cl upload will call this hook after the issue is created/modified.
    449 
    450   This hook does the following:
    451   * Adds a link to preview docs changes if there are any docs changes in the CL.
    452   * Adds 'NOTRY=true' if the CL contains only docs changes.
    453   * Adds 'NOTREECHECKS=true' for non master branch changes since they do not
    454     need to be gated on the master branch's tree.
    455   * Adds 'NOTRY=true' for non master branch changes since trybots do not yet
    456     work on them.
    457   * Adds 'NOPRESUBMIT=true' for non master branch changes since those don't
    458     run the presubmit checks.
    459   * Adds extra trybots for the paths defined in PATH_TO_EXTRA_TRYBOTS.
    460   """
    461 
    462   results = []
    463   atleast_one_docs_change = False
    464   all_docs_changes = True
    465   for affected_file in change.AffectedFiles():
    466     affected_file_path = affected_file.LocalPath()
    467     file_path, _ = os.path.splitext(affected_file_path)
    468     if 'site' == file_path.split(os.path.sep)[0]:
    469       atleast_one_docs_change = True
    470     else:
    471       all_docs_changes = False
    472     if atleast_one_docs_change and not all_docs_changes:
    473       break
    474 
    475   issue = cl.issue
    476   if issue:
    477     original_description = cl.GetDescription()
    478     changeIdLine = None
    479     if cl.IsGerrit():
    480       # Remove Change-Id from description and add it back at the end.
    481       regex = re.compile(r'^(Change-Id: (\w+))(\n*)\Z', re.M | re.I)
    482       changeIdLine = re.search(regex, original_description).group(0)
    483       original_description = re.sub(regex, '', original_description)
    484       original_description = re.sub('\n+\Z', '\n', original_description)
    485 
    486     new_description = original_description
    487 
    488     # If the change includes only doc changes then add NOTRY=true in the
    489     # CL's description if it does not exist yet.
    490     if all_docs_changes and not re.search(
    491         r'^NOTRY=true$', new_description, re.M | re.I):
    492       new_description += '\nNOTRY=true'
    493       results.append(
    494           output_api.PresubmitNotifyResult(
    495               'This change has only doc changes. Automatically added '
    496               '\'NOTRY=true\' to the CL\'s description'))
    497 
    498     # If there is atleast one docs change then add preview link in the CL's
    499     # description if it does not already exist there.
    500     if atleast_one_docs_change and not re.search(
    501         r'^DOCS_PREVIEW=.*', new_description, re.M | re.I):
    502       # Automatically add a link to where the docs can be previewed.
    503       new_description += '\nDOCS_PREVIEW= %s%s' % (DOCS_PREVIEW_URL, issue)
    504       results.append(
    505           output_api.PresubmitNotifyResult(
    506               'Automatically added a link to preview the docs changes to the '
    507               'CL\'s description'))
    508 
    509     # If the target ref is not master then add NOTREECHECKS=true and NOTRY=true
    510     # to the CL's description if it does not already exist there.
    511     target_ref = cl.GetRemoteBranch()[1]
    512     if target_ref != 'refs/remotes/origin/master':
    513       if not re.search(
    514           r'^NOTREECHECKS=true$', new_description, re.M | re.I):
    515         new_description += "\nNOTREECHECKS=true"
    516         results.append(
    517             output_api.PresubmitNotifyResult(
    518                 'Branch changes do not need to rely on the master branch\'s '
    519                 'tree status. Automatically added \'NOTREECHECKS=true\' to the '
    520                 'CL\'s description'))
    521       if not re.search(
    522           r'^NOTRY=true$', new_description, re.M | re.I):
    523         new_description += "\nNOTRY=true"
    524         results.append(
    525             output_api.PresubmitNotifyResult(
    526                 'Trybots do not yet work for non-master branches. '
    527                 'Automatically added \'NOTRY=true\' to the CL\'s description'))
    528       if not re.search(
    529           r'^NOPRESUBMIT=true$', new_description, re.M | re.I):
    530         new_description += "\nNOPRESUBMIT=true"
    531         results.append(
    532             output_api.PresubmitNotifyResult(
    533                 'Branch changes do not run the presubmit checks.'))
    534 
    535     # Automatically set CQ_INCLUDE_TRYBOTS if any of the changed files here
    536     # begin with the paths of interest.
    537     cq_master_to_trybots = collections.defaultdict(set)
    538     for affected_file in change.AffectedFiles():
    539       affected_file_path = affected_file.LocalPath()
    540       for path_prefix, extra_bots in PATH_PREFIX_TO_EXTRA_TRYBOTS.iteritems():
    541         if affected_file_path.startswith(path_prefix):
    542           results.append(
    543               output_api.PresubmitNotifyResult(
    544                   'Your CL modifies the path %s.\nAutomatically adding %s to '
    545                   'the CL description.' % (affected_file_path, extra_bots)))
    546           _MergeCQExtraTrybotsMaps(
    547               cq_master_to_trybots, _GetCQExtraTrybotsMap(extra_bots))
    548     if cq_master_to_trybots:
    549       new_description = _AddCQExtraTrybotsToDesc(
    550           cq_master_to_trybots, new_description)
    551 
    552     # If the description has changed update it.
    553     if new_description != original_description:
    554       if changeIdLine:
    555         # The Change-Id line must have two newlines before it.
    556         new_description += '\n\n' + changeIdLine
    557       cl.UpdateDescription(new_description)
    558 
    559     return results
    560 
    561 
    562 def _AddCQExtraTrybotsToDesc(cq_master_to_trybots, description):
    563   """Adds the specified master and trybots to the CQ_INCLUDE_TRYBOTS keyword.
    564 
    565   If the keyword already exists in the description then it appends to it only
    566   if the specified values do not already exist.
    567   If the keyword does not exist then it creates a new section in the
    568   description.
    569   """
    570   match = re.search(r'^CQ_INCLUDE_TRYBOTS=(.*)$', description, re.M | re.I)
    571   if match:
    572     original_trybots_map = _GetCQExtraTrybotsMap(match.group(1))
    573     _MergeCQExtraTrybotsMaps(cq_master_to_trybots, original_trybots_map)
    574     new_description = description.replace(
    575         match.group(0), _GetCQExtraTrybotsStr(cq_master_to_trybots))
    576   else:
    577     new_description = description + "\n%s" % (
    578         _GetCQExtraTrybotsStr(cq_master_to_trybots))
    579   return new_description
    580 
    581 
    582 def _MergeCQExtraTrybotsMaps(dest_map, map_to_be_consumed):
    583   """Merges two maps of masters to trybots into one."""
    584   for master, trybots in map_to_be_consumed.iteritems():
    585     dest_map[master].update(trybots)
    586   return dest_map
    587 
    588 
    589 def _GetCQExtraTrybotsMap(cq_extra_trybots_str):
    590   """Parses CQ_INCLUDE_TRYBOTS str and returns a map of masters to trybots."""
    591   cq_master_to_trybots = collections.defaultdict(set)
    592   for section in cq_extra_trybots_str.split(';'):
    593     if section:
    594       master, bots = section.split(':')
    595       cq_master_to_trybots[master].update(bots.split(','))
    596   return cq_master_to_trybots
    597 
    598 
    599 def _GetCQExtraTrybotsStr(cq_master_to_trybots):
    600   """Constructs the CQ_INCLUDE_TRYBOTS str from a map of masters to trybots."""
    601   sections = []
    602   for master, trybots in cq_master_to_trybots.iteritems():
    603     sections.append('%s:%s' % (master, ','.join(trybots)))
    604   return 'CQ_INCLUDE_TRYBOTS=%s' % ';'.join(sections)
    605 
    606 
    607 def CheckChangeOnCommit(input_api, output_api):
    608   """Presubmit checks for the change on commit.
    609 
    610   The following are the presubmit checks:
    611   * Check change has one and only one EOL.
    612   * Ensures that the Skia tree is open in
    613     http://skia-tree-status.appspot.com/. Shows a warning if it is in 'Caution'
    614     state and an error if it is in 'Closed' state.
    615   """
    616   results = []
    617   results.extend(_CommonChecks(input_api, output_api))
    618   results.extend(
    619       _CheckTreeStatus(input_api, output_api, json_url=(
    620           SKIA_TREE_STATUS_URL + '/banner-status?format=json')))
    621   results.extend(_CheckLGTMsForPublicAPI(input_api, output_api))
    622   results.extend(_CheckOwnerIsInAuthorsFile(input_api, output_api))
    623   return results
    624