fix(clock): dedup tasks lock bug removal

polylan_submitter/clock/tests.py

@@ -0,0 +1,57 @@
+from unittest import mock
+
+from django.core.cache import cache
+from django.test import TestCase, override_settings
+
+from events.models import Event
+from games.models import EventGame, Game
+
+from .tasks import HEARTBEAT_LOCK_KEY, clock_heartbeat_task, start_clock_heartbeat
+
+LOCMEM_CACHE = {"default": {"BACKEND": "django.core.cache.backends.locmem.LocMemCache"}}
+
+
+@override_settings(CACHES=LOCMEM_CACHE)
+@mock.patch("clock.tasks.get_channel_layer")
+class ClockHeartbeatTests(TestCase):
+    def setUp(self):
+        cache.clear()
+        event = Event.objects.create(name="Event", path="event")
+        clock = Game.objects.create(name="Clock", path="clock", custom_path=True)
+        self.event_game = EventGame.objects.create(event=event, game=clock)
+        cache.clear()  # post_save signal can start a chain
+
+    @mock.patch("clock.tasks.clock_heartbeat_task")
+    def test_only_one_chain_is_started(self, task, _):
+        start_clock_heartbeat()
+        start_clock_heartbeat()
+
+        task.enqueue.assert_called_once_with(cache.get(HEARTBEAT_LOCK_KEY))
+
+    def test_owning_chain_reschedules_itself(self, channel_layer):
+        channel_layer.return_value.group_send = mock.AsyncMock()
+        cache.set(HEARTBEAT_LOCK_KEY, "chain")
+        with mock.patch("clock.tasks.clock_heartbeat_task") as patched:
+            clock_heartbeat_task.call("chain")
+
+        patched.using.return_value.enqueue.assert_called_once_with("chain")
+        channel_layer.return_value.group_send.assert_awaited_once()
+        self.assertEqual(cache.get(HEARTBEAT_LOCK_KEY), "chain")
+
+    def test_superseded_chain_stops(self, channel_layer):
+        cache.set(HEARTBEAT_LOCK_KEY, "new-chain")
+        with mock.patch("clock.tasks.clock_heartbeat_task") as patched:
+            clock_heartbeat_task.call("old-chain")
+
+        patched.using.assert_not_called()
+        channel_layer.assert_not_called()
+        self.assertEqual(cache.get(HEARTBEAT_LOCK_KEY), "new-chain")
+
+    def test_chain_dies_and_releases_lock_when_game_disabled(self, _):
+        EventGame.objects.filter(pk=self.event_game.pk).update(enabled=False)
+        cache.set(HEARTBEAT_LOCK_KEY, "chain")
+        with mock.patch("clock.tasks.clock_heartbeat_task") as patched:
+            clock_heartbeat_task.call("chain")
+
+        patched.using.assert_not_called()
+        self.assertIsNone(cache.get(HEARTBEAT_LOCK_KEY))