MPD: Improve seek impl and add seekid impl. Add tests which fails.

docs/changes.rst

@@ -46,6 +46,7 @@ greatly improved MPD client support.
     ``single`` without quotes to work better with BitMPC.
   - Fixed delete current playing track from playlist, which crashed several
     clients.
+  - Implement ``seek`` and ``seekid``.
 
 - Backends:
 

mopidy/frontends/mpd/protocol/playback.py

@@ -293,6 +293,8 @@ def seek(frontend, songpos, seconds):
         Seeks to the position ``TIME`` (in seconds) of entry ``SONGPOS`` in
         the playlist.
     """
+    if frontend.backend.playback.current_playlist_position != songpos:
+        playpos(frontend, songpos)
     return frontend.backend.playback.seek(int(seconds) * 1000)
 
 @handle_pattern(r'^seekid "(?P<cpid>\d+)" "(?P<seconds>\d+)"$')
@@ -304,7 +306,9 @@ def seekid(frontend, cpid, seconds):
 
         Seeks to the position ``TIME`` (in seconds) of song ``SONGID``.
     """
-    raise MpdNotImplemented # TODO
+    if frontend.backend.playback.current_cpid != cpid:
+        playid(frontend, cpid)
+    return frontend.backend.playback.seek(int(seconds) * 1000)
 
 @handle_pattern(r'^setvol "(?P<volume>[-+]*\d+)"$')
 def setvol(frontend, volume):

tests/frontends/mpd/playback_test.py

@@ -271,12 +271,18 @@ class PlaybackControlHandlerTest(unittest.TestCase):
         self.assert_(u'OK' in result)
 
     def test_seek(self):
+        self.b.current_playlist.load([Track()])
+        self.h.handle_request(u'seek "0"')
         result = self.h.handle_request(u'seek "0" "30"')
-        self.assert_(u'ACK [0@0] {} Not implemented' in result)
+        self.assert_(u'OK' in result)
+        self.assert_(self.b.playback.time_position > 30000)
 
     def test_seekid(self):
+        self.b.current_playlist.load([Track()])
         result = self.h.handle_request(u'seekid "0" "30"')
-        self.assert_(u'ACK [0@0] {} Not implemented' in result)
+        self.assert_(u'OK' in result)
+        self.assert_(self.b.playback.time_position > 30000)
+
 
     def test_stop(self):
         result = self.h.handle_request(u'stop')