fix(gateway): tolerate cancelled channel tasks during shutdown

nanobot/channels/manager.py

@@ -252,6 +252,10 @@ class ChannelManager:
             try:
                 await channel.stop()
                 logger.info("Stopped {} channel", name)
+            except asyncio.CancelledError:
+                if asyncio.current_task() and asyncio.current_task().cancelling():
+                    raise
+                logger.debug("Channel {} stop task was already cancelled", name)
             except Exception:
                 logger.exception("Error stopping {}", name)
 

nanobot/channels/websocket.py

@@ -827,6 +827,10 @@ class WebSocketChannel(BaseChannel):
         if self._server_task:
             try:
                 await self._server_task
+            except asyncio.CancelledError:
+                if asyncio.current_task() and asyncio.current_task().cancelling():
+                    raise
+                self.logger.debug("server task was already cancelled during shutdown")
             except Exception as e:
                 self.logger.warning("server task error during shutdown: {}", e)
             self._server_task = None

tests/channels/test_channel_plugins.py

@@ -1222,6 +1222,43 @@ async def test_stop_all_handles_channel_exception():
     assert mgr._dispatch_task is None
 
 
+@pytest.mark.asyncio
+async def test_stop_all_handles_channel_stop_cancelled_task():
+    """stop_all should treat a channel's already-cancelled internals as stopped."""
+
+    class _StopCancelledChannel(BaseChannel):
+        name = "stopcancelled"
+        display_name = "Stop Cancelled"
+
+        async def start(self) -> None:
+            pass
+
+        async def stop(self) -> None:
+            raise asyncio.CancelledError("server task cancelled")
+
+        async def send(self, msg: OutboundMessage) -> None:
+            pass
+
+    fake_config = SimpleNamespace(
+        channels=ChannelsConfig(),
+        providers=SimpleNamespace(groq=SimpleNamespace(api_key="")),
+    )
+
+    mgr = ChannelManager.__new__(ChannelManager)
+    mgr.config = fake_config
+    mgr.bus = MessageBus()
+    next_channel = _StartableChannel(fake_config, mgr.bus)
+    mgr.channels = {
+        "stopcancelled": _StopCancelledChannel(fake_config, mgr.bus),
+        "next": next_channel,
+    }
+    mgr._dispatch_task = None
+
+    await mgr.stop_all()
+
+    assert next_channel.stopped is True
+
+
 @pytest.mark.asyncio
 async def test_start_all_no_channels_logs_warning():
     """start_all should log warning when no channels are enabled."""

tests/channels/test_websocket_channel.py

@@ -96,6 +96,27 @@ def _basic_handler(bus: Any, **kw: Any) -> GatewayServices:
     )
 
 
+@pytest.mark.asyncio
+async def test_stop_treats_cancelled_server_task_as_shutdown() -> None:
+    channel = _ch(MessageBus())
+    channel._running = True
+    channel._stop_event = asyncio.Event()
+
+    async def _server_task() -> None:
+        await asyncio.Event().wait()
+
+    task = asyncio.create_task(_server_task())
+    await asyncio.sleep(0)
+    task.cancel()
+    await asyncio.sleep(0)
+    channel._server_task = task
+
+    await channel.stop()
+
+    assert channel._server_task is None
+    assert task.cancelled()
+
+
 @pytest.fixture()
 def bus() -> MagicMock:
     b = MagicMock()