mpd: Add 'seekcur' command

docs/changes.rst

@@ -8,7 +8,9 @@ This change log is used to track all major changes to Mopidy.
 v0.11.0 (in development)
 ========================
 
-- No changes yet.
+**MPD frontend**
+
+- Add support for ``seekcur`` command added in MPD 0.17.
 
 
 v0.10.0 (2012-12-12)

mopidy/frontends/mpd/protocol/playback.py

@@ -349,6 +349,26 @@ def seekid(context, tlid, seconds):
     context.core.playback.seek(int(seconds) * 1000).get()
 
 
+@handle_request(r'^seekcur "(?P<position>\d+)"$')
+@handle_request(r'^seekcur "(?P<diff>[-+]\d+)"$')
+def seekcur(context, position=None, diff=None):
+    """
+    *musicpd.org, playback section:*
+
+        ``seekcur {TIME}``
+
+        Seeks to the position ``TIME`` within the current song. If prefixed by
+        '+' or '-', then the time is relative to the current playing position.
+    """
+    if position is not None:
+        position = int(position) * 1000
+        context.core.playback.seek(position).get()
+    elif diff is not None:
+        position = context.core.playback.time_position.get()
+        position += int(diff) * 1000
+        context.core.playback.seek(position).get()
+
+
 @handle_request(r'^setvol (?P<volume>[-+]*\d+)$')
 @handle_request(r'^setvol "(?P<volume>[-+]*\d+)"$')
 def setvol(context, volume):

tests/frontends/mpd/protocol/playback_test.py

@@ -414,6 +414,37 @@ class PlaybackControlHandlerTest(protocol.BaseTestCase):
         self.assertEqual(seek_track, self.core.playback.current_track.get())
         self.assertInResponse('OK')
 
+    def test_seekcur_absolute_value(self):
+        self.core.tracklist.add([Track(uri='dummy:a', length=40000)])
+        self.core.playback.play()
+
+        self.sendRequest('seekcur "30"')
+
+        self.assertGreaterEqual(self.core.playback.time_position.get(), 30000)
+        self.assertInResponse('OK')
+
+    def test_seekcur_positive_diff(self):
+        self.core.tracklist.add([Track(uri='dummy:a', length=40000)])
+        self.core.playback.play()
+        self.core.playback.seek(10000)
+        self.assertGreaterEqual(self.core.playback.time_position.get(), 10000)
+
+        self.sendRequest('seekcur "+20"')
+
+        self.assertGreaterEqual(self.core.playback.time_position.get(), 30000)
+        self.assertInResponse('OK')
+
+    def test_seekcur_negative_diff(self):
+        self.core.tracklist.add([Track(uri='dummy:a', length=40000)])
+        self.core.playback.play()
+        self.core.playback.seek(30000)
+        self.assertGreaterEqual(self.core.playback.time_position.get(), 30000)
+
+        self.sendRequest('seekcur "-20"')
+
+        self.assertLessEqual(self.core.playback.time_position.get(), 15000)
+        self.assertInResponse('OK')
+
     def test_stop(self):
         self.sendRequest('stop')
         self.assertEqual(STOPPED, self.core.playback.state.get())