Fix get(_input)_users in ChatAction with no service msg

tests/telethon/events/test_chataction.py

@@ -0,0 +1,67 @@
+import pytest
+
+from telethon import TelegramClient, events, types, utils
+
+
+def get_client():
+    return TelegramClient(None, 1, '1')
+
+
+def get_user_456():
+    return types.User(
+        id=456,
+        access_hash=789,
+        first_name='User 123'
+    )
+
+
+@pytest.mark.asyncio
+async def test_get_input_users_no_action_message_no_entities():
+    event = events.ChatAction.build(types.UpdateChatParticipantDelete(
+        chat_id=123,
+        user_id=456,
+        version=1
+    ))
+    event._set_client(get_client())
+
+    assert await event.get_input_users() == []
+
+
+@pytest.mark.asyncio
+async def test_get_input_users_no_action_message():
+    user = get_user_456()
+    event = events.ChatAction.build(types.UpdateChatParticipantDelete(
+        chat_id=123,
+        user_id=456,
+        version=1
+    ))
+    event._set_client(get_client())
+    event._entities[user.id] = user
+
+    assert await event.get_input_users() == [utils.get_input_peer(user)]
+
+
+@pytest.mark.asyncio
+async def test_get_users_no_action_message_no_entities():
+    event = events.ChatAction.build(types.UpdateChatParticipantDelete(
+        chat_id=123,
+        user_id=456,
+        version=1
+    ))
+    event._set_client(get_client())
+
+    assert await event.get_users() == []
+
+
+@pytest.mark.asyncio
+async def test_get_users_no_action_message():
+    user = get_user_456()
+    event = events.ChatAction.build(types.UpdateChatParticipantDelete(
+        chat_id=123,
+        user_id=456,
+        version=1
+    ))
+    event._set_client(get_client())
+    event._entities[user.id] = user
+
+    assert await event.get_users() == [user]