Raise Exception if there's no bot instance in context

tests/test_message.py

@@ -0,0 +1,47 @@
+from asyncio import BaseEventLoop
+
+import pytest
+
+from aiogram import Bot, types
+from . import FakeTelegram, TOKEN
+
+pytestmark = pytest.mark.asyncio
+
+
+@pytest.yield_fixture()
+async def bot(event_loop):
+    """ Bot fixture """
+    _bot = Bot(TOKEN, loop=event_loop, parse_mode=types.ParseMode.HTML)
+    yield _bot
+    await _bot.close()
+
+
+@pytest.yield_fixture()
+async def message(bot, event_loop):
+    """
+    Message fixture
+    :param bot: Telegram bot fixture
+    :type bot: Bot
+    :param event_loop: asyncio event loop
+    :type event_loop: BaseEventLoop
+    """
+    from .types.dataset import MESSAGE
+    msg = types.Message(**MESSAGE)
+
+    async with FakeTelegram(message_dict=MESSAGE, loop=event_loop):
+        _message = await bot.send_message(chat_id=msg.chat.id, text=msg.text)
+
+    yield _message
+
+
+class TestMiscCases:
+    async def test_calling_bot_not_from_context(self, message):
+        """
+        Calling any helper method without bot instance in context.
+
+        :param message: message fixture
+        :type message: types.Message
+        :return: RuntimeError with reason and help
+        """
+        with pytest.raises(RuntimeError):
+            await message.edit_text('test_calling_bot_not_from_context')