models: Add type specific constructors to Ref

mopidy/models.py

@@ -175,6 +175,36 @@ class Ref(ImmutableObject):
     #: Constant used for comparision with the :attr:`type` field.
     TRACK = 'track'
 
+    @classmethod
+    def album(cls, **kwargs):
+        """Create a :class:`Ref` with ``type`` :attr:`ALBUM`."""
+        kwargs['type'] = Ref.ALBUM
+        return cls(**kwargs)
+
+    @classmethod
+    def artist(cls, **kwargs):
+        """Create a :class:`Ref` with ``type`` :attr:`ARTIST`."""
+        kwargs['type'] = Ref.ARTIST
+        return cls(**kwargs)
+
+    @classmethod
+    def directory(cls, **kwargs):
+        """Create a :class:`Ref` with ``type`` :attr:`DIRECTORY`."""
+        kwargs['type'] = Ref.DIRECTORY
+        return cls(**kwargs)
+
+    @classmethod
+    def playlist(cls, **kwargs):
+        """Create a :class:`Ref` with ``type`` :attr:`PLAYLIST`."""
+        kwargs['type'] = Ref.PLAYLIST
+        return cls(**kwargs)
+
+    @classmethod
+    def track(cls, **kwargs):
+        """Create a :class:`Ref` with ``type`` :attr:`TRACK`."""
+        kwargs['type'] = Ref.TRACK
+        return cls(**kwargs)
+
 
 class Artist(ImmutableObject):
     """

tests/models_test.py

@@ -94,6 +94,36 @@ class RefTest(unittest.TestCase):
         self.assertEqual(Ref.PLAYLIST, 'playlist')
         self.assertEqual(Ref.TRACK, 'track')
 
+    def test_album_constructor(self):
+        ref = Ref.album(uri='foo', name='bar')
+        self.assertEqual(ref.uri, 'foo')
+        self.assertEqual(ref.name, 'bar')
+        self.assertEqual(ref.type, Ref.ALBUM)
+
+    def test_artist_constructor(self):
+        ref = Ref.artist(uri='foo', name='bar')
+        self.assertEqual(ref.uri, 'foo')
+        self.assertEqual(ref.name, 'bar')
+        self.assertEqual(ref.type, Ref.ARTIST)
+
+    def test_directory_constructor(self):
+        ref = Ref.directory(uri='foo', name='bar')
+        self.assertEqual(ref.uri, 'foo')
+        self.assertEqual(ref.name, 'bar')
+        self.assertEqual(ref.type, Ref.DIRECTORY)
+
+    def test_playlist_constructor(self):
+        ref = Ref.playlist(uri='foo', name='bar')
+        self.assertEqual(ref.uri, 'foo')
+        self.assertEqual(ref.name, 'bar')
+        self.assertEqual(ref.type, Ref.PLAYLIST)
+
+    def test_track_constructor(self):
+        ref = Ref.track(uri='foo', name='bar')
+        self.assertEqual(ref.uri, 'foo')
+        self.assertEqual(ref.name, 'bar')
+        self.assertEqual(ref.type, Ref.TRACK)
+
 
 class ArtistTest(unittest.TestCase):
     def test_uri(self):