refactor playlist duplicate error structure

- use non_field_errors struct when writing duplicate track errors
- generalize frontend error handler and update frontend error parsing

api/tests/playlists/test_models.py

@@ -124,6 +124,139 @@ def test_insert_many_honor_max_tracks(preferences, factories):
         playlist.insert_many([track, track, track])
 
 
+def test_can_insert_duplicate_by_default(factories):
+    playlist = factories["playlists.Playlist"]()
+    track = factories["music.Track"]()
+    factories["playlists.PlaylistTrack"](playlist=playlist, index=0, track=track)
+
+    new = factories["playlists.PlaylistTrack"](playlist=playlist, index=1, track=track)
+    playlist.insert(new)
+
+    new.refresh_from_db()
+    assert new.index == 1
+
+
+def test_cannot_insert_duplicate(factories):
+    playlist = factories["playlists.Playlist"](name="playlist")
+    track = factories["music.Track"]()
+
+    factories["playlists.PlaylistTrack"](playlist=playlist, index=0, track=track)
+
+    with pytest.raises(exceptions.ValidationError) as e:
+        new = factories["playlists.PlaylistTrack"](
+            playlist=playlist, index=1, track=track
+        )
+        playlist.insert(new, allow_duplicates=False)
+
+    errors = e.value.detail["non_field_errors"]
+    assert len(errors) == 1
+
+    err = errors[0]
+    assert err["code"] == "tracks_already_exist_in_playlist"
+    assert err["playlist_name"] == "playlist"
+    assert err["tracks"] == [track.title]
+
+
+def test_can_insert_track_to_playlist_with_existing_duplicates(factories):
+    playlist = factories["playlists.Playlist"]()
+    existing_duplicate = factories["music.Track"]()
+    factories["playlists.PlaylistTrack"](
+        playlist=playlist, index=0, track=existing_duplicate
+    )
+    factories["playlists.PlaylistTrack"](
+        playlist=playlist, index=1, track=existing_duplicate
+    )
+    factories["playlists.PlaylistTrack"](
+        playlist=playlist, index=2, track=existing_duplicate
+    )
+
+    new_track = factories["music.Track"]()
+    new_plt = factories["playlists.PlaylistTrack"](
+        playlist=playlist, index=3, track=new_track
+    )
+
+    # no error
+    playlist.insert(new_plt, allow_duplicates=False)
+
+
+def test_can_insert_duplicate_with_override(factories):
+    playlist = factories["playlists.Playlist"]()
+    track = factories["music.Track"]()
+    factories["playlists.PlaylistTrack"](playlist=playlist, index=0, track=track)
+
+    new = factories["playlists.PlaylistTrack"](playlist=playlist, index=1, track=track)
+    playlist.insert(new, allow_duplicates=True)
+
+    new.refresh_from_db()
+    assert new.index == 1
+
+
+def test_can_insert_many_duplicates_by_default(factories):
+    playlist = factories["playlists.Playlist"]()
+
+    t1 = factories["music.Track"]()
+    factories["playlists.PlaylistTrack"](playlist=playlist, index=0, track=t1)
+
+    t2 = factories["music.Track"]()
+    factories["playlists.PlaylistTrack"](playlist=playlist, index=1, track=t2)
+
+    t4 = factories["music.Track"]()
+
+    tracks = [t1, t4, t2]
+
+    plts = playlist.insert_many(tracks)
+
+    assert len(plts) == 3
+    assert plts[0].track == t1
+    assert plts[1].track == t4
+    assert plts[2].track == t2
+
+
+def test_cannot_insert_many_duplicates(factories):
+    playlist = factories["playlists.Playlist"](name="playlist")
+
+    t1 = factories["music.Track"]()
+    factories["playlists.PlaylistTrack"](playlist=playlist, index=0, track=t1)
+
+    t2 = factories["music.Track"]()
+    factories["playlists.PlaylistTrack"](playlist=playlist, index=1, track=t2)
+
+    t4 = factories["music.Track"]()
+
+    with pytest.raises(exceptions.ValidationError) as e:
+        tracks = [t1, t4, t2]
+        playlist.insert_many(tracks, allow_duplicates=False)
+
+    errors = e.value.detail["non_field_errors"]
+    assert len(errors) == 1
+
+    err = errors[0]
+    assert err["code"] == "tracks_already_exist_in_playlist"
+    assert err["playlist_name"] == "playlist"
+    assert err["tracks"] == [t1.title, t2.title]
+
+
+def test_can_insert_many_duplicates_with_override(factories):
+    playlist = factories["playlists.Playlist"]()
+
+    t1 = factories["music.Track"]()
+    factories["playlists.PlaylistTrack"](playlist=playlist, index=0, track=t1)
+
+    t2 = factories["music.Track"]()
+    factories["playlists.PlaylistTrack"](playlist=playlist, index=1, track=t2)
+
+    t4 = factories["music.Track"]()
+
+    tracks = [t1, t4, t2]
+
+    plts = playlist.insert_many(tracks, allow_duplicates=True)
+
+    assert len(plts) == 3
+    assert plts[0].track == t1
+    assert plts[1].track == t4
+    assert plts[2].track == t2
+
+
 @pytest.mark.parametrize(
     "privacy_level,expected", [("me", False), ("instance", False), ("everyone", True)]
 )

api/tests/playlists/test_serializers.py

@@ -24,7 +24,7 @@ def test_create_insert_is_called_when_index_is_None(factories, mocker):
     assert serializer.is_valid() is True
 
     plt = serializer.save()
-    insert.assert_called_once_with(playlist, plt, None)
+    insert.assert_called_once_with(playlist, plt, None, True)
     assert plt.index == 0
 
 
@@ -41,7 +41,7 @@ def test_create_insert_is_called_when_index_is_provided(factories, mocker):
 
     plt = serializer.save()
     first.refresh_from_db()
-    insert.assert_called_once_with(playlist, plt, 0)
+    insert.assert_called_once_with(playlist, plt, 0, True)
     assert plt.index == 0
     assert first.index == 1
 
@@ -60,11 +60,35 @@ def test_update_insert_is_called_when_index_is_provided(factories, mocker):
 
     plt = serializer.save()
     first.refresh_from_db()
-    insert.assert_called_once_with(playlist, plt, 0)
+    insert.assert_called_once_with(playlist, plt, 0, True)
     assert plt.index == 0
     assert first.index == 1
 
 
+def test_update_insert_is_called_with_duplicate_override_when_duplicates_allowed(
+    factories, mocker
+):
+    playlist = factories["playlists.Playlist"]()
+    plt = factories["playlists.PlaylistTrack"](playlist=playlist, index=0)
+    insert = mocker.spy(models.Playlist, "insert")
+    factories["playlists.Playlist"]()
+    factories["music.Track"]()
+
+    serializer = serializers.PlaylistTrackWriteSerializer(
+        plt,
+        data={
+            "playlist": playlist.pk,
+            "track": plt.track.pk,
+            "index": 0,
+            "allow_duplicates": True,
+        },
+    )
+    assert serializer.is_valid() is True
+    plt = serializer.save()
+
+    insert.assert_called_once_with(playlist, plt, 0, True)
+
+
 def test_playlist_serializer_include_covers(factories, api_request):
     playlist = factories["playlists.Playlist"]()
     t1 = factories["music.Track"]()