fix(gateway): avoid false failure reactions on restart cancellation

gateway/platforms/base.py

@@ -502,6 +502,14 @@ class MessageType(Enum):
     COMMAND = "command"  # /command style
 
 
+class ProcessingOutcome(Enum):
+    """Result classification for message-processing lifecycle hooks."""
+
+    SUCCESS = "success"
+    FAILURE = "failure"
+    CANCELLED = "cancelled"
+
+
 @dataclass
 class MessageEvent:
     """
@@ -625,6 +633,7 @@ class BasePlatformAdapter(ABC):
         # Gateway shutdown cancels these so an old gateway instance doesn't keep
         # working on a task after --replace or manual restarts.
         self._background_tasks: set[asyncio.Task] = set()
+        self._expected_cancelled_tasks: set[asyncio.Task] = set()
         # Chats where auto-TTS on voice input is disabled (set by /voice off)
         self._auto_tts_disabled_chats: set = set()
         # Chats where typing indicator is paused (e.g. during approval waits).
@@ -1133,7 +1142,7 @@ class BasePlatformAdapter(ABC):
     async def on_processing_start(self, event: MessageEvent) -> None:
         """Hook called when background processing begins."""
 
-    async def on_processing_complete(self, event: MessageEvent, success: bool) -> None:
+    async def on_processing_complete(self, event: MessageEvent, outcome: ProcessingOutcome) -> None:
         """Hook called when background processing completes."""
 
     async def _run_processing_hook(self, hook_name: str, *args: Any, **kwargs: Any) -> None:
@@ -1352,6 +1361,7 @@ class BasePlatformAdapter(ABC):
             return
         if hasattr(task, "add_done_callback"):
             task.add_done_callback(self._background_tasks.discard)
+            task.add_done_callback(self._expected_cancelled_tasks.discard)
     
     @staticmethod
     def _get_human_delay() -> float:
@@ -1580,7 +1590,11 @@ class BasePlatformAdapter(ABC):
 
             # Determine overall success for the processing hook
             processing_ok = delivery_succeeded if delivery_attempted else not bool(response)
-            await self._run_processing_hook("on_processing_complete", event, processing_ok)
+            await self._run_processing_hook(
+                "on_processing_complete",
+                event,
+                ProcessingOutcome.SUCCESS if processing_ok else ProcessingOutcome.FAILURE,
+            )
 
             # Check if there's a pending message that was queued during our processing
             if session_key in self._pending_messages:
@@ -1599,10 +1613,14 @@ class BasePlatformAdapter(ABC):
                 return  # Already cleaned up
                 
         except asyncio.CancelledError:
-            await self._run_processing_hook("on_processing_complete", event, False)
+            current_task = asyncio.current_task()
+            outcome = ProcessingOutcome.CANCELLED
+            if current_task is None or current_task not in self._expected_cancelled_tasks:
+                outcome = ProcessingOutcome.FAILURE
+            await self._run_processing_hook("on_processing_complete", event, outcome)
             raise
         except Exception as e:
-            await self._run_processing_hook("on_processing_complete", event, False)
+            await self._run_processing_hook("on_processing_complete", event, ProcessingOutcome.FAILURE)
             logger.error("[%s] Error handling message: %s", self.name, e, exc_info=True)
             # Send the error to the user so they aren't left with radio silence
             try:
@@ -1646,10 +1664,12 @@ class BasePlatformAdapter(ABC):
         """
         tasks = [task for task in self._background_tasks if not task.done()]
         for task in tasks:
+            self._expected_cancelled_tasks.add(task)
             task.cancel()
         if tasks:
             await asyncio.gather(*tasks, return_exceptions=True)
         self._background_tasks.clear()
+        self._expected_cancelled_tasks.clear()
         self._pending_messages.clear()
         self._active_sessions.clear()