Implement track_for_id to allow fetching singletons by discogs id

Author: snejus

beetsplug/discogs.py

@@ -241,6 +241,14 @@ def album_for_id(self, album_id: str) -> AlbumInfo | None:
             return None
         return self.get_album_info(result)
 
+    def track_for_id(self, track_id: str) -> TrackInfo | None:
+        if album := self.album_for_id(track_id):
+            for track in album.tracks:
+                if track.track_id == track_id:
+                    return track
+
+        return None
+
     def get_albums(self, query: str) -> Iterable[AlbumInfo]:
         """Returns a list of AlbumInfo objects for a discogs search query."""
         # Strip non-word characters from query. Things like "!" and "-" can

docs/changelog.rst

@@ -19,6 +19,9 @@ New features:
   Media Session API to customize media notifications.
 * :doc:`plugins/discogs`: Add configurable ``search_limit`` option to
   limit the number of results returned by the Discogs metadata search queries.
+* :doc:`plugins/discogs`: Implement ``track_for_id`` method to allow retrieving
+  singletons by their Discogs ID.
+  :bug:`4661`
 
 Bug fixes: