Keep a reference to tasks

docs/userguide/testing.rst

@@ -42,7 +42,7 @@ Create a ``tests`` directory at the root of the project directory and create a m
                 client = ClientComponent("Hello!")
                 await client.start(ctx)
 
-        event_loop.create_task(run())
+        task = event_loop.create_task(run())
         with pytest.raises(SystemExit) as exc:
             event_loop.run_forever()
 

examples/tutorial1/tests/test_client_server.py

@@ -21,7 +21,7 @@ async def run() -> None:
             client = ClientComponent("Hello!")
             await client.start(ctx)
 
-    event_loop.create_task(run())
+    task = event_loop.create_task(run())
     with pytest.raises(SystemExit) as exc:
         event_loop.run_forever()
 

src/asphalt/core/event.py

@@ -109,6 +109,7 @@ def __init__(
                 event_class, Event
             ), "event_class must be a subclass of Event"
             self.bound_signals: MutableMapping[Any, Signal] = WeakKeyDictionary()
+        self._background_tasks = set()
 
     def __get__(self, instance, owner) -> Signal:
         if instance is None:
@@ -225,7 +226,9 @@ async def do_dispatch() -> None:
         future = loop.create_future()
         if self.listeners:
             listeners = list(self.listeners)
-            loop.create_task(do_dispatch())
+            task = loop.create_task(do_dispatch())
+            self._background_tasks.add(task)
+            task.add_done_callback(self._background_tasks.discard)
         else:
             future.set_result(True)