Increment version for every timeplaylist is set

mopidy/backends/__init__.py

@@ -17,8 +17,18 @@ class BaseBackend(object):
 class BaseCurrentPlaylistController(object):
     def __init__(self, backend):
         self.backend = backend
+        self.version = 0
         self.playlist = Playlist()
 
+    def get_playlist(self):
+        return self._playlist
+
+    def set_playlist(self, playlist):
+        self._playlist = playlist
+        self.version += 1
+
+    playlist = property(get_playlist, set_playlist)
+
     def add(self, uri, at_position=None):
         raise NotImplementedError
 

tests/backends/__init__.py

@@ -111,6 +111,13 @@ class BaseCurrentPlaylistControllerTest(object):
         self.assertEqual(tracks[0], shuffled_tracks[0])
         self.assertEqual(set(tracks), set(shuffled_tracks))
 
+    def test_version(self):
+        version = self.controller.version
+
+        self.controller.playlist = Playlist()
+
+        self.assertEqual(version+1, self.controller.version)
+
 class BasePlaybackControllerTest(object):
     uris = []
     backend_class = None