Bug 1660506 - Drop the 'remove_on_projects' feature from the Backstop optimization, r=marco

In the past, the 'backstop' optimization was applied to tasks by default across
all projects, even though it only really made sense on autoland. To choose what
would happen on non-autoland branches, we invented this 'remove_on_projects'
concept.

These days, we only apply the backstop optimization in the first place for
autoland. So 'remove_on_projects' is no longer necessary.

Depends on D88149

Differential Revision: https://phabricator.services.mozilla.com/D88150

taskcluster/taskgraph/optimize/backstop.py

@@ -5,7 +5,6 @@
 from __future__ import absolute_import, print_function, unicode_literals
 
 from taskgraph.optimize import OptimizationStrategy, register_strategy
-from taskgraph.util.attributes import match_run_on_projects
 from taskgraph.util.backstop import is_backstop, BACKSTOP_PUSH_INTERVAL, BACKSTOP_TIME_INTERVAL
 
 
@@ -20,23 +19,12 @@ class Backstop(OptimizationStrategy):
         push_interval (int): Number of pushes
         time_interval (int): Minutes between forced schedules.
                              Use 0 to disable.
-        remove_on_projects (set): For non-autoland projects, the task will
-            be removed if we're running on one of these projects, otherwise
-            it will be kept.
     """
     def __init__(self, push_interval, time_interval, remove_on_projects=None):
         self.push_interval = push_interval
         self.time_interval = time_interval
-        self.remove_on_projects = remove_on_projects or {'try'}
 
     def should_remove_task(self, task, params, _):
-        project = params["project"]
-
-        # Scheduling on a backstop only makes sense on autoland. For other projects,
-        # remove the task if the project matches self.remove_on_projects.
-        if project != 'autoland':
-            return match_run_on_projects(project, self.remove_on_projects)
-
         if is_backstop(params, self.push_interval, self.time_interval):
             return False
         return True

taskcluster/taskgraph/test/test_optimize_strategies.py

@@ -312,7 +312,7 @@ def test_bugbug_fallback(monkeypatch, responses, params):
 
 def test_backstop(responses, params):
     all_labels = {t.label for t in default_tasks}
-    opt = Backstop(10, 60, {'try'})  # every 10th push or 1 hour
+    opt = Backstop(10, 60)  # every 10th push or 1 hour
 
     responses.add(
         responses.GET,
@@ -357,15 +357,6 @@ def test_backstop(responses, params):
     scheduled = {t.label for t in default_tasks if not opt.should_remove_task(t, params, None)}
     assert scheduled == all_labels
 
-    # On non-autoland projects the 'remove_on_projects' value is used.
-    params['project'] = 'mozilla-central'
-    scheduled = {t.label for t in default_tasks if not opt.should_remove_task(t, params, None)}
-    assert scheduled == all_labels
-
-    params['project'] = 'try'
-    scheduled = {t.label for t in default_tasks if not opt.should_remove_task(t, params, None)}
-    assert scheduled == set()
-
 
 if __name__ == '__main__':
     main()