Wake deadline consumers on enqueue instead of polling every second

server/packages/tavolo-platform/tests/test_store.py

@@ -270,6 +270,17 @@ class InMemoryGameStoreTest(unittest.TestCase):
         self.assertEqual(60.0, await store.next_deadline())
         self.assertEqual(["b"], await store.due_deadlines(now=100.0))
 
+    @async_test
+    async def test_deadline_notifications_reach_subscribers(self) -> None:
+        store = InMemoryGameStore(_registry())
+        async with store.subscribe_deadlines() as events:
+            await store.notify_deadline()
+            signal = await asyncio.wait_for(anext(events), timeout=1.0)
+            self.assertIsNone(signal)
+        # The subscription is gone after the context exits: notifying
+        # again is a no-op rather than an error.
+        await store.notify_deadline()
+
 
 class RedisGameStoreTest(unittest.TestCase):
     @async_test