updates

python-backend/tests/test_player.py

@@ -125,6 +125,29 @@ async def test_play_from_start_starts_the_first_track(
     assert only(seen, PlaybackChanged)[-1].playing is True
 
 
+async def test_switching_albums_while_playing_announces_the_new_track(
+    bus: EventBus, player: FakePlayer, seen: list[Event]
+) -> None:
+    """Regression: starting a new playlist from track 0 while already playing track 0
+    of the previous one used to look like a no-op index change, so no ``TrackChanged``
+    went out and front-ends never learned the album had switched."""
+    player.set_playlist(playlist(name="fuchs"))
+    player.play_from_start()
+    await bus.drain()
+
+    player.set_playlist(playlist(name="eule"))
+    player.play_from_start()
+    await bus.drain()
+
+    assert player.is_playing
+    assert player.playlist is not None
+    assert player.playlist.name == "eule"
+    changes = only(seen, TrackChanged)
+    assert changes[-1].index == 0
+    assert changes[-1].track is not None
+    assert changes[-1].track.path.parent.name == "eule"
+
+
 async def test_playing_an_empty_playlist_does_nothing(
     bus: EventBus, player: FakePlayer, caplog: pytest.LogCaptureFixture
 ) -> None: