add tests for MediaGroup middleware

tests/test_dispatcher/test_middlewares/test_media_group.py

@@ -0,0 +1,86 @@
+import asyncio
+
+from aiogram.dispatcher.middlewares.media_group import MediaGroupAggregatorMiddleware
+from aiogram.types import Message, Chat
+from datetime import datetime
+from typing import Any
+import pytest
+
+class TestMediaGroupAggregatorMiddleware:
+    def _get_message(self, message_id: int, **kwargs):
+        chat = Chat(id=1, type="private", title="Test")
+        return Message(message_id=message_id, date=datetime.now(), chat=chat, **kwargs)
+
+
+    def get_middleware(self):
+        return MediaGroupAggregatorMiddleware(delay=0.1)
+
+    async def test_skip_non_media_group(self):
+        is_called = False
+        async def next_handler(*args, **kwargs):
+            nonlocal is_called
+            is_called = True
+        await self.get_middleware()(next_handler, self._get_message(1), {})
+        assert is_called
+
+    async def test_called_once_for_album(self):
+        middleware = self.get_middleware()
+        counter = 0
+        album = None
+        async def next_handler(_, data: dict[str, Any]):
+            nonlocal counter, album
+            counter += 1
+            album = data.get("album")
+        await asyncio.gather(
+            middleware(next_handler, self._get_message(1, media_group_id="42"), {}),
+            middleware(next_handler, self._get_message(2, media_group_id="42"), {})
+        )
+        assert album is not None
+        assert len(album) == 2
+        assert counter == 1
+
+    async def test_propagate_first_media_in_album(self):
+        middleware = self.get_middleware()
+        first_message = None
+        async def next_handler(message: Message, _):
+            nonlocal first_message
+            first_message = message
+        await asyncio.gather(
+            middleware(next_handler, self._get_message(2, media_group_id="42"), {}),
+            middleware(next_handler, self._get_message(1, media_group_id="42"), {})
+        )
+        assert isinstance(first_message, Message)
+        assert first_message.message_id == 1
+
+    async def test_different_albums_non_interfere(self):
+        middleware = self.get_middleware()
+        counter = 0
+        albums = []
+        async def next_handler(_, data: dict[str, Any]):
+            nonlocal counter, albums
+            counter += 1
+            albums.append(data.get("album"))
+        await asyncio.gather(
+            middleware(next_handler, self._get_message(1, media_group_id="1"), {}),
+            middleware(next_handler, self._get_message(2, media_group_id="2"), {})
+        )
+        assert counter == 2
+        assert len(albums) == 2
+
+    async def test_retry_handling(self):
+        middleware = self.get_middleware()
+        album = None
+        async def failed_handler(*args, **kwargs):
+            raise Exception("Failed")
+        async def working_handler(_, data: dict[str, Any]):
+            nonlocal album
+            album = data.get("album")
+        first_message = self._get_message(1, media_group_id="42")
+        second_message = self._get_message(2, media_group_id="42")
+        with pytest.raises(Exception):
+            await asyncio.gather(
+                middleware(failed_handler, first_message, {}),
+                middleware(failed_handler, second_message, {})
+            )
+        await middleware(working_handler, first_message, {})
+        assert len(album) == 2