Bug 1636271 - [taskgraph] Set autoland optimizations via per-project parameter, r=tomprince

This creates a new set of optimization strategies
(taskgraph.optimize:project.autoland) to use with autoland. Among other things,
it also means there's no need for the 'test-try' optimization as the autoland
strategies are no longer the default behaviour.

Differential Revision: https://phabricator.services.mozilla.com/D79705

taskcluster/taskgraph/decision.py

@@ -72,6 +72,10 @@ PER_PROJECT_PARAMETERS = {
         'target_tasks_method': 'graphics_tasks',
     },
 
+    'autoland': {
+        'optimize_strategies': 'taskgraph.optimize:project.autoland',
+    },
+
     'mozilla-central': {
         'target_tasks_method': 'default',
         'release_type': 'nightly',

taskcluster/taskgraph/optimize/__init__.py

@@ -397,11 +397,12 @@ class Alias(CompositeStrategy):
 
 
 def split_bugbug_arg(arg):
-    """
-    The bugbug optimization strageies require passing an dict as
-    scratch space for communicating with downstream stratgies.
-    This function pass the provided argument to the first strategy,
-    and a fresh dictionary to the second stratgey.
+    """Split args for bugbug based strategies.
+
+    Many bugbug based optimizations require passing an empty dict by reference
+    to communicate to downstream strategies. This function passes the provided
+    arg to the first strategy and an empty dict to second (bugbug based)
+    strategy.
     """
     return (arg, {})
 
@@ -417,15 +418,24 @@ register_strategy('build-optimized', args=(
     'backstop',
 ))(All)
 register_strategy('build-fuzzing', args=('push-interval-10',))(Alias)
-register_strategy('test', args=(
-    Any('skip-unless-schedules', 'bugbug-reduced-fallback', split_args=split_bugbug_arg),
-    'backstop',
-))(All)
+register_strategy('test', args=('skip-unless-schedules',))(Alias)
 register_strategy('test-inclusive', args=('skip-unless-schedules',))(Alias)
-register_strategy('test-try', args=('skip-unless-schedules',))(Alias)
 
 
-# Strategy overrides used by |mach try| and/or shadow-scheduler tasks.
+# Strategy overrides used to tweak the default strategies. These are referenced
+# by the `optimize_strategies` parameter.
+
+class project(object):
+    """Strategies that should be applied per-project."""
+
+    autoland = {
+        'test': All(
+            Any('skip-unless-schedules', 'bugbug-reduced-fallback', split_args=split_bugbug_arg),
+            'backstop',
+        ),
+    }
+    """Strategy overrides that apply to autoland."""
+
 
 class experimental(object):
     """Experimental strategies either under development or used as benchmarks.

taskcluster/taskgraph/transforms/tests.py

@@ -1817,9 +1817,6 @@ def make_job_description(config, tasks):
             jobdesc['when'] = task['when']
         elif 'optimization' in task:
             jobdesc['optimization'] = task['optimization']
-        # Pushes generated by `mach try auto` should use the non-try optimizations.
-        elif config.params.is_try() and config.params['try_mode'] != 'try_auto':
-            jobdesc['optimization'] = {'test-try': schedules}
         elif set(schedules) & set(INCLUSIVE_COMPONENTS):
             jobdesc['optimization'] = {'test-inclusive': schedules}
         else:

taskcluster/taskgraph/util/schema.py

@@ -225,7 +225,6 @@ OptimizationSchema = voluptuous.Any(
     # optimize strategy aliases for the test kind
     {'test': list(schedules.ALL_COMPONENTS)},
     {'test-inclusive': list(schedules.ALL_COMPONENTS)},
-    {'test-try': list(schedules.ALL_COMPONENTS)},
 )
 
 # shortcut for a string where task references are allowed