fix(telegram): support using inject decorator on BaseHandler.handle

Author: notypecheck

aioinject/ext/aiogram.py

@@ -3,6 +3,7 @@
 from typing import Any
 
 from aiogram import BaseMiddleware, Router
+from aiogram.handlers import BaseHandler
 from aiogram.types import TelegramObject
 
 import aioinject
@@ -20,16 +21,21 @@ class _ContextGetter:
     def __init__(self, *, remove_from_args: bool) -> None:
         self.remove_from_args = remove_from_args
 
-    def __call__(
-        self, args: tuple[Any], kwargs: dict[str, Any]
+    def __call__(  # noqa: C901
+        self,
+        args: tuple[Any],
+        kwargs: dict[str, Any],
     ) -> aioinject.Context:
         if _ARG_NAME in kwargs:  # pragma: no cover
             if self.remove_from_args:
                 return kwargs.pop(_ARG_NAME)
             return kwargs[_ARG_NAME]
 
         # Try to find a dict-like looking object (in case it's a middleware)
-        for arg in args:
+        for arg_pos, arg in enumerate(args):
+            # BaseHandler.handle is being called
+            if arg_pos == 0 and isinstance(arg, BaseHandler):
+                arg = arg.data  # noqa: PLW2901
             if not isinstance(arg, dict):
                 continue
             if _ARG_NAME in arg:

tests/integrations/test_aiogram.py

@@ -3,6 +3,7 @@
 
 import pytest
 from aiogram import BaseMiddleware, Router
+from aiogram.handlers import MessageHandler
 from aiogram.types import TelegramObject
 
 import aioinject
@@ -36,6 +37,17 @@ async def handler(
     await middleware(handler=handler, event=event_, data=data_)  # type: ignore[arg-type]
 
 
+async def test_class_handler(container: Container) -> None:
+    class MyHandler(MessageHandler):
+        @inject
+        async def handle(self, number: Injected[int] = INJECTED) -> Any:
+            return number
+
+    async with container.context() as ctx:
+        handler = MyHandler(object(), aioinject_context=ctx)  # type: ignore[arg-type]
+        assert await handler.handle() is await container.root.resolve(int)
+
+
 async def test_can_inject_into_middleware(container: Container) -> None:
     class CustomMiddleware(BaseMiddleware):
         @inject