fix: await any awaitable callback return value, not only coroutines (#168)

tests/test_models.py

@@ -199,6 +199,7 @@ class AttrAccessModel(MixinBase, UUIDMixin, WatchedFieldsMixin):
 
 
 _sync_events: list[dict] = []
+_future_events: list[str] = []
 
 
 @watch("status")
@@ -219,6 +220,20 @@ class SyncCallbackModel(MixinBase, UUIDMixin, WatchedFieldsMixin):
         _sync_events.append({"event": "update", "changes": changes})
 
 
+class FutureCallbackModel(MixinBase, UUIDMixin, WatchedFieldsMixin):
+    """Model whose on_create returns an asyncio.Task (awaitable, not a coroutine)."""
+
+    __tablename__ = "mixin_future_callback_models"
+
+    name: Mapped[str] = mapped_column(String(50))
+
+    def on_create(self) -> "asyncio.Task[None]":
+        async def _work() -> None:
+            _future_events.append("created")
+
+        return asyncio.ensure_future(_work())
+
+
 @pytest.fixture(scope="function")
 async def mixin_session():
     engine = create_async_engine(DATABASE_URL, echo=False)
@@ -1108,6 +1123,28 @@ class TestSyncCallbacks:
         assert updates[0]["changes"]["status"] == {"old": "initial", "new": "updated"}
 
 
+class TestFutureCallbacks:
+    """Callbacks returning a non-coroutine awaitable (asyncio.Task / Future)."""
+
+    @pytest.fixture(autouse=True)
+    def clear_events(self):
+        _future_events.clear()
+        yield
+        _future_events.clear()
+
+    @pytest.mark.anyio
+    async def test_task_callback_is_awaited(self, mixin_session):
+        """on_create returning an asyncio.Task is awaited and its work completes."""
+        obj = FutureCallbackModel(name="test")
+        mixin_session.add(obj)
+        await mixin_session.commit()
+        # Two turns: one for _run() to execute, one for the inner _work() task.
+        await asyncio.sleep(0)
+        await asyncio.sleep(0)
+
+        assert _future_events == ["created"]
+
+
 class TestAttributeAccessInCallbacks:
     """Verify that self attributes are accessible inside every callback type.