Bug 1524358 - get commit message locally, rather than from task parameters r=tomprince

Differential Revision: https://phabricator.services.mozilla.com/D18288

--HG--
extra : moz-landing-system : lando

.taskcluster.yml

@@ -13,7 +13,7 @@
 # - cron tasks - See taskcluster/taskgraph/cron/decision.py
 #   {
 #     tasks_for: 'cron',
-#     push: {revision, pushlog_id, pushdate, owner, comment}
+#     push: {revision, pushlog_id, pushdate, owner}
 #     repository: {url, project, level},
 #     cron: {task_id, job_name, job_symbol, quoted_args},
 #     now,
@@ -191,7 +191,6 @@ tasks:
                 GECKO_HEAD_REPOSITORY: '${repoUrl}'
                 GECKO_HEAD_REF: '${push.revision}'
                 GECKO_HEAD_REV: '${push.revision}'
-                GECKO_COMMIT_MSG: {$if: 'tasks_for != "action"', then: '${push.comment}'}
                 HG_STORE_PATH: /builds/worker/checkouts/hg-store
                 TASKCLUSTER_CACHES: /builds/worker/checkouts
                 # someday, these will be provided by the worker - Bug 1492664
@@ -240,7 +239,6 @@ tasks:
                   --pushlog-id='${push.pushlog_id}'
                   --pushdate='${push.pushdate}'
                   --project='${repository.project}'
-                  --message="$GECKO_COMMIT_MSG"
                   --owner='${ownerEmail}'
                   --level='${repository.level}'
                   --base-repository="$GECKO_BASE_REPOSITORY"

taskcluster/mach_commands.py

@@ -149,9 +149,6 @@ class MachCommands(MachCommandBase):
     @CommandArgument('--comm-head-rev',
                      required=False,
                      help='Commit revision to use from head comm-* repository')
-    @CommandArgument('--message',
-                     required=True,
-                     help='Commit message to be parsed. Example: "try: -b do -p all -u all"')
     @CommandArgument('--project',
                      required=True,
                      help='Project to use for creating task graph. Example: --project=try')

taskcluster/taskgraph/cron/decision.py

@@ -59,7 +59,6 @@ def make_decision_task(params, root, symbol, arguments=[]):
             'pushlog_id': push_info['pushid'],
             'pushdate': push_info['pushdate'],
             'owner': 'cron',
-            'comment': '',
         },
         'cron': {
             'task_id': os.environ.get('TASK_ID', '<cron task id>'),

taskcluster/taskgraph/decision.py

@@ -20,7 +20,7 @@ from .parameters import Parameters, get_version, get_app_version
 from .taskgraph import TaskGraph
 from .try_option_syntax import parse_message
 from .util.schema import validate_schema, Schema
-from taskgraph.util.hg import get_hg_revision_branch
+from taskgraph.util.hg import get_hg_revision_branch, get_hg_commit_message
 from taskgraph.util.partials import populate_release_history
 from taskgraph.util.yaml import load_yaml
 from voluptuous import Required, Optional
@@ -193,7 +193,6 @@ def get_decision_parameters(config, options):
         'head_repository',
         'head_rev',
         'head_ref',
-        'message',
         'project',
         'pushlog_id',
         'pushdate',
@@ -222,6 +221,7 @@ def get_decision_parameters(config, options):
     parameters['build_number'] = 1
     parameters['version'] = get_version(product_dir)
     parameters['app_version'] = get_app_version(product_dir)
+    parameters['message'] = get_hg_commit_message(GECKO)
     parameters['hg_branch'] = get_hg_revision_branch(GECKO, revision=parameters['head_rev'])
     parameters['next_version'] = None
     parameters['release_type'] = ''

taskcluster/taskgraph/test/test_decision.py

@@ -87,8 +87,9 @@ class TestGetDecisionParameters(unittest.TestCase):
         self.assertEqual(params['owner'], 'ffxbld@noreply.mozilla.org')
 
     @patch('taskgraph.decision.get_hg_revision_branch')
-    def test_try_options(self, _):
-        self.options['message'] = 'try: -b do -t all'
+    @patch('taskgraph.decision.get_hg_commit_message')
+    def test_try_options(self, mock_get_hg_commit_message, _):
+        mock_get_hg_commit_message.return_value = 'try: -b do -t all'
         self.options['project'] = 'try'
         with MockedOpen({self.ttc_file: None}):
             params = decision.get_decision_parameters(FAKE_GRAPH_CONFIG, self.options)

taskcluster/taskgraph/util/hg.py

@@ -47,8 +47,12 @@ def get_hg_revision_branch(root, revision):
     ], cwd=root)
 
 
+# For these functions, we assume that run-task has correctly checked out the
+# revision indicated by GECKO_HEAD_REF, so all that remains is to see what the
+# current revision is.  Mercurial refers to that as `.`.
+def get_hg_commit_message(root):
+    return subprocess.check_output(['hg', 'log', '-r', '.', '-T', '{desc}'], cwd=root)
+
+
 def calculate_head_rev(root):
-    # we assume that run-task has correctly checked out the revision indicated by
-    # GECKO_HEAD_REF, so all that remains is to see what the current revision is.
-    # Mercurial refers to that as `.`.
     return subprocess.check_output(['hg', 'log', '-r', '.', '-T', '{node}'], cwd=root)