easynetwork_asyncio.ThreadsPortal: Fix future returned by run_coroutine_soon()

src/easynetwork_asyncio/threads.py

@@ -85,7 +85,21 @@ def schedule_task() -> concurrent.futures.Future[_T]:
             future: concurrent.futures.Future[_T] = concurrent.futures.Future()
 
             async def coroutine() -> None:
+                def on_fut_done(future: concurrent.futures.Future[_T]) -> None:
+                    if future.cancelled():
+                        try:
+                            self.run_sync(task.cancel)
+                        except RuntimeError:
+                            # on_fut_done() called from coroutine()
+                            # or the portal is already shut down
+                            pass
+
+                task = TaskUtils.current_asyncio_task()
                 try:
+                    if future.cancelled():
+                        task.cancel()
+                    else:
+                        future.add_done_callback(on_fut_done)
                     result = await coro_func(*args, **kwargs)
                 except asyncio.CancelledError:
                     future.cancel()
@@ -102,20 +116,9 @@ async def coroutine() -> None:
 
             task = self.__task_group.create_task(coroutine())
             loop = task.get_loop()
+            del task
             with self.__lock.get():
                 loop.call_soon(self.__register_waiter(self.__call_soon_waiters, loop).set_result, None)
-
-            def on_fut_done(future: concurrent.futures.Future[_T]) -> None:
-                if future.cancelled():
-                    try:
-                        self.run_sync(task.cancel)
-                    except RuntimeError:
-                        # on_fut_done() called from coroutine()
-                        # or the portal is already shut down
-                        pass
-
-            future.add_done_callback(on_fut_done)
-
             return future
 
         return self.run_sync(schedule_task)

tests/functional_test/test_async/test_backend/test_asyncio_backend.py

@@ -973,6 +973,43 @@ def thread() -> None:
 
         cancellation_ignored.assert_called_once()
 
+    async def test____create_threads_portal____run_coroutine_soon____future_cancelled_before_await(
+        self,
+        event_loop: asyncio.AbstractEventLoop,
+        backend: AsyncIOBackend,
+    ) -> None:
+        checkpoints: list[str] = []
+
+        async def coroutine() -> None:
+            current_task = asyncio.current_task()
+            assert current_task is not None
+
+            checkpoints.append(f"{current_task.cancelling()=}")
+            await asyncio.sleep(0)
+            checkpoints.append("does-not-raise-CancelledError")
+
+        def thread() -> None:
+            future = threads_portal.run_coroutine_soon(coroutine)
+            future.cancel()
+
+            wait_concurrent_futures({future}, timeout=5)  # Test if future.set_running_or_notify_cancel() have been called
+            assert future.cancelled()
+
+        event_loop_slowdown_handle: asyncio.Handle
+
+        def event_loop_slowdown() -> None:  # Drastically slow down event loop
+            nonlocal event_loop_slowdown_handle
+
+            time.sleep(0.5)
+            event_loop_slowdown_handle = event_loop.call_soon(event_loop_slowdown)
+
+        event_loop_slowdown_handle = event_loop.call_soon(event_loop_slowdown)
+        async with backend.create_threads_portal() as threads_portal:
+            await backend.run_in_thread(thread)
+
+        event_loop_slowdown_handle.cancel()
+        assert checkpoints == ["current_task.cancelling()=1"]
+
     async def test____create_threads_portal____context_exit____wait_scheduled_call_soon(
         self,
         event_loop: asyncio.AbstractEventLoop,