Fix on_ready and the scheduler waiting for the first room event

matrix/bot.py

@@ -5,7 +5,7 @@
 
 from typing import Optional, Any
 
-from nio import AsyncClient, Event, MatrixRoom
+from nio import AsyncClient, Event, MatrixRoom, SyncResponse
 
 from .room import Room, make_room
 from .space import Space
@@ -297,6 +297,7 @@ def _load_config(self, config: Config | str) -> None:
         self.register_command(self.help)
 
         self.client.add_event_callback(self._on_matrix_event, Event)
+        self.client.add_response_callback(self._on_sync, SyncResponse)
         self._auto_register_events()
 
     def start(self, *, config: Config | str) -> None:
@@ -351,15 +352,16 @@ async def run(self) -> None:
     async def _wait_until_synced(self) -> None:
         await self._synced.wait()
 
+    async def _on_sync(self, _response: SyncResponse) -> None:
+        """Mark the bot as synced once a sync with the homeserver completes."""
+        self._synced.set()
+
     # MATRIX EVENTS
 
     async def on_message(self, room: Room, event: Event) -> None:
         await self._process_commands(room, event)
 
     async def _on_matrix_event(self, matrix_room: MatrixRoom, event: Event) -> None:
-        if not self._synced.is_set():
-            self._synced.set()
-
         # ignore bot events
         if event.sender == self.client.user:
             return

tests/test_bot.py

@@ -1,7 +1,7 @@
 import pytest
 
 from unittest.mock import AsyncMock, MagicMock, patch
-from nio import MatrixRoom, RoomMessageText, LoginError
+from nio import MatrixRoom, RoomMessageText, LoginError, SyncResponse
 
 from matrix import Bot, Config, Context, Extension, Room, Space
 from matrix.errors import (
@@ -720,6 +720,47 @@ def test_start_handles_keyboard_interrupt(caplog):
     bot._client.close.assert_awaited_once()
 
 
+def test_load_config_registers_sync_response_callback():
+    bot = Bot()
+    bot._load_config(Config(username="grace", password="grace1234"))
+
+    assert any(
+        cb.func == bot._on_sync and cb.filter is SyncResponse
+        for cb in bot.client.response_callbacks
+    )
+
+
+@pytest.mark.asyncio
+async def test_room_event_does_not_mark_synced(bot, room, event):
+    with patch.object(bot, "_dispatch_matrix_event", new_callable=AsyncMock):
+        await bot._on_matrix_event(room, event)
+
+    assert not bot._synced.is_set()
+
+
+@pytest.mark.asyncio
+async def test_run_becomes_ready_after_first_sync_without_room_events(bot_with_token):
+    async def sync_forever(**_kwargs):
+        # A completed sync with no room events, then the loop keeps going.
+        await bot_with_token._on_sync(MagicMock(spec=SyncResponse))
+        await asyncio.Event().wait()
+
+    bot_with_token._client.sync_forever = AsyncMock(side_effect=sync_forever)
+    bot_with_token._on_ready = AsyncMock()
+    bot_with_token.scheduler.start = MagicMock()
+
+    task = asyncio.create_task(bot_with_token.run())
+
+    await asyncio.wait_for(bot_with_token._synced.wait(), timeout=1.0)
+    await asyncio.sleep(0)
+
+    task.cancel()
+    await asyncio.gather(task, return_exceptions=True)
+
+    bot_with_token._on_ready.assert_awaited_once()
+    bot_with_token.scheduler.start.assert_called_once()
+
+
 @pytest.mark.asyncio
 async def test_on_ready_called_only_once(bot):
     # Prepare