Add volume test

mopidy/backends/__init__.py

@@ -103,6 +103,7 @@ class BasePlaybackController(object):
     def __init__(self, backend):
         self.backend = backend
         self.current_track = None
+        self._volume = None
 
     def play(self, id=None, position=None):
         raise NotImplementedError
@@ -146,3 +147,7 @@ class BasePlaybackController(object):
             return playlist.tracks.index(self.current_track)
         except ValueError:
             return None
+
+    @property
+    def volume(self):
+        return self._volume

mopidy/backends/gstreamer.py

@@ -87,3 +87,11 @@ class GStreamerPlaybackController(BasePlaybackController):
         else:
             next_track = playlist.tracks[self.playlist_position+1]
             self.play(next_track)
+
+    @property
+    def volume(self):
+        return self.bin.get_property('volume') * 100
+
+    @volume.setter
+    def volume(self, value):
+        return self.bin.set_property('volume', float(value) / 100)

tests/backends/basetests.py

@@ -190,6 +190,7 @@ class BaseCurrentPlaylistControllerTest(object):
 class BasePlaybackControllerTest(object):
     uris = []
     backend_class = None
+    supports_volume = False
 
     def setUp(self):
         self.backend = self.backend_class()
@@ -369,7 +370,14 @@ class BasePlaybackControllerTest(object):
         raise NotImplementedError
 
     def test_volume(self):
-        raise NotImplementedError
+        if not self.supports_volume:
+            self.assertEqual(self.playback.volume, None)
+        else:
+            self.assertEqual(self.playback.volume, 100)
+            self.playback.volume = 50
+            self.assertEqual(self.playback.volume, 50)
+            self.playback.volume = 0
+            self.assertEqual(self.playback.volume, 0)
 
     def test_play_with_consume(self):
         raise NotImplementedError

tests/backends/gstreamer.py

@@ -20,6 +20,7 @@ class GStreamerPlaybackControllerTest(BasePlaybackControllerTest, unittest.TestC
            ]
 
     backend_class = GStreamerBackend
+    supports_volume = True
 
 if __name__ == '__main__':
     unittest.main()