HandlerObject: Unwrap handler before awaitable check (#435)

* Unwrap handler before awaitable check

* Remove unused 'type:ignore' comment

* Add wrapped handler tests

aiogram/dispatcher/event/handler.py

@@ -61,7 +61,8 @@ class HandlerObject(CallableMixin):
 
     def __post_init__(self) -> None:
         super(HandlerObject, self).__post_init__()
-        if inspect.isclass(self.callback) and issubclass(self.callback, BaseHandler):  # type: ignore
+        callback = inspect.unwrap(self.callback)
+        if inspect.isclass(callback) and issubclass(callback, BaseHandler):
             self.awaitable = True
 
     async def check(self, *args: Any, **kwargs: Any) -> Tuple[bool, Dict[str, Any]]:

tests/test_dispatcher/test_handler/test_base.py

@@ -1,11 +1,13 @@
 import asyncio
 import datetime
+from functools import wraps
 from typing import Any
 
 import pytest
 
 from aiogram import Bot
 from aiogram.api.types import Chat, Message, Update
+from aiogram.dispatcher.event.handler import HandlerObject
 from aiogram.dispatcher.handler.base import BaseHandler
 
 
@@ -56,3 +58,9 @@ class TestBaseClassBasedHandler:
 
         assert handler.event == event
         assert handler.update == update
+
+    @pytest.mark.asyncio
+    async def test_wrapped_handler(self):
+        # wrap the handler on dummy function
+        handler = wraps(MyHandler)(lambda: None)
+        assert HandlerObject(handler).awaitable is True