core: Make tracklist.append() return the appended TlTracks

docs/changes.rst

@@ -111,6 +111,11 @@ backends:
 - The Spotify backend now returns the track if you search for the Spotify track
   URI. (Fixes: :issue:`233`)
 
+- :meth:`mopidy.core.TracklistController.append` now returns a list of the
+  :class:`mopidy.models.TlTrack` instances that was added to the tracklist.
+  This makes it easier to start playing one of the tracks that was just
+  appended to the tracklist.
+
 **Bug fixes**
 
 - :issue:`218`: The MPD commands ``listplaylist`` and ``listplaylistinfo`` now

mopidy/core/tracklist.py

@@ -92,13 +92,17 @@ class TracklistController(object):
 
         :param tracks: tracks to append
         :type tracks: list of :class:`mopidy.models.Track`
+        :rtype: list of class:`mopidy.models.TlTrack`
         """
+        tl_tracks = []
         for track in tracks:
-            self.add(track, increase_version=False)
+            tl_tracks.append(self.add(track, increase_version=False))
 
         if tracks:
             self.version += 1
 
+        return tl_tracks
+
     def clear(self):
         """Clear the current playlist."""
         self._tl_tracks = []

tests/backends/base/tracklist.py

@@ -153,10 +153,13 @@ class TracklistControllerTest(object):
         self.assertEqual(self.playback.state, PlaybackState.STOPPED)
         self.assertEqual(self.playback.current_track, None)
 
+    @populate_playlist
+    def test_append_returns_the_tl_tracks_that_was_added(self):
+        tl_tracks = self.controller.append(self.controller.tracks[1:2])
+        self.assertEqual(tl_tracks[0][1], self.controller.tracks[1])
+
     def test_index_returns_index_of_track(self):
-        tl_tracks = []
-        for track in self.tracks:
-            tl_tracks.append(self.controller.add(track))
+        tl_tracks = self.controller.append(self.tracks)
         self.assertEquals(0, self.controller.index(tl_tracks[0]))
         self.assertEquals(1, self.controller.index(tl_tracks[1]))
         self.assertEquals(2, self.controller.index(tl_tracks[2]))