Bug 1383880: Annotate builds and tests with SCHEDULES-related optimizations; r=ahal

This means that a push to try affecting only Android will only run android builds
and tests, for example.

MozReview-Commit-ID: HVUvIg0EUZn

--HG--
extra : rebase_source : 67b38061d9c7e533b2347eaacf6b186d9b86b984
extra : histedit_source : 7b01445b822e8fc7f04d74cd37006240da33ecc6

taskcluster/taskgraph/transforms/build_attrs.py

@@ -4,6 +4,7 @@
 from __future__ import absolute_import, print_function, unicode_literals
 
 from taskgraph.transforms.base import TransformSequence
+from taskgraph.util.platforms import platform_family
 
 transforms = TransformSequence()
 
@@ -31,3 +32,18 @@ def set_build_attributes(config, jobs):
         })
 
         yield job
+
+
+@transforms.add
+def set_schedules_optimization(config, jobs):
+    """Set the `skip-unless-affected` optimization based on the build platform."""
+    for job in jobs:
+        # don't add skip-unless-schedules if there's already a when defined
+        if 'when' in job:
+            yield job
+            continue
+
+        build_platform = job['attributes']['build_platform']
+        job.setdefault('optimization',
+                       {'skip-unless-schedules': [platform_family(build_platform)]})
+        yield job

taskcluster/taskgraph/transforms/tests.py

@@ -22,6 +22,7 @@ from __future__ import absolute_import, print_function, unicode_literals
 from taskgraph.transforms.base import TransformSequence
 from taskgraph.util.schema import resolve_keyed_by
 from taskgraph.util.treeherder import split_symbol, join_symbol
+from taskgraph.util.platforms import platform_family
 from taskgraph.util.schema import (
     validate_schema,
     optionally_keyed_by,
@@ -930,12 +931,16 @@ def make_job_description(config, tests):
             'platform': test.get('treeherder-machine-platform', test['build-platform']),
         }
 
-        # run SETA unless this is a try push
-        if config.params['project'] == 'try':
-            jobdesc['when'] = test.get('when', {})
+        if test.get('when'):
+            jobdesc['when'] = test['when']
         else:
-            # when SETA is enabled, the 'when' does not apply (optimizations don't mix)
-            jobdesc['optimization'] = {'seta': None}
+            schedules = [platform_family(test['build-platform'])]
+            if config.params['project'] != 'try':
+                # for non-try branches, include SETA
+                jobdesc['optimization'] = {'skip-unless-schedules-or-seta': schedules}
+            else:
+                # otherwise just use skip-unless-schedules
+                jobdesc['optimization'] = {'skip-unless-schedules': schedules}
 
         run = jobdesc['run'] = {}
         run['using'] = 'mozharness-test'

taskcluster/taskgraph/util/platforms.py

@@ -0,0 +1,20 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from __future__ import absolute_import, print_function, unicode_literals
+
+import re
+
+# platform family is extracted from build platform by taking the alphabetic prefix
+# and then translating win -> windows
+_platform_re = re.compile(r'^[a-z]*')
+_renames = {
+    'win': 'windows'
+}
+
+
+def platform_family(build_platform):
+    """Given a build platform, return the platform family (linux, macosx, etc.)"""
+    family = _platform_re.match(build_platform).group(0)
+    return _renames.get(family, family)