Added test that prove previous fix

tests/test_issues/test_bot_context_is_usable.py

@@ -0,0 +1,27 @@
+from datetime import datetime
+
+from aiogram import Dispatcher, Router
+from aiogram.enums import ChatType
+from aiogram.filters import Command
+from aiogram.methods import SendMessage
+from aiogram.types import Chat, Message, Update, User
+from tests.mocked_bot import MockedBot
+
+issue_router = Router()
+
+
+@issue_router.message(Command("test"))
+async def my_handler(message: Message):
+    await message.answer("PASS")
+    return True
+
+
+async def test_something(bot: MockedBot):
+    dp = Dispatcher()
+    dp.include_router(issue_router)
+    bot.add_result_for(method=SendMessage, ok=True)
+    chat = Chat(id=666, type=ChatType.PRIVATE)
+    user = User(id=666, is_bot=False, first_name="User")
+    msg = Message(message_id=1, date=datetime.now(), from_user=user, chat=chat, text="/test")
+    result = await dp.feed_update(bot, Update(message=msg, update_id=1))
+    assert result is True