mpd: Add listfiles command skeleton

docs/changelog.rst

@@ -60,13 +60,22 @@ MPD frontend
 - Add "not implemented" skeletons of new commands in the MPD protocol version
   0.19:
 
-  - ``rangeid``
-  - ``addtagid``
-  - ``cleartagid``
-  - ``mount``
-  - ``unmount``
-  - ``listmounts``
-  - ``listneighbors``
+  - Current playlist:
+
+    - ``rangeid``
+    - ``addtagid``
+    - ``cleartagid``
+
+  - Mounts and neighbors:
+
+    - ``mount``
+    - ``unmount``
+    - ``listmounts``
+    - ``listneighbors``
+
+  - Music DB:
+
+    - ``listfiles``
 
 File backend
 ------------

mopidy/mpd/protocol/music_db.py

@@ -349,6 +349,29 @@ def listallinfo(context, uri=None):
     return result
 
 
+@protocol.commands.add('listfiles')
+def listfiles(context, uri=None):
+    """
+    *musicpd.org, music database section:*
+
+        ``listfiles [URI]``
+
+        Lists the contents of the directory URI, including files are not
+        recognized by MPD. URI can be a path relative to the music directory or
+        an URI understood by one of the storage plugins. The response contains
+        at least one line for each directory entry with the prefix "file: " or
+        "directory: ", and may be followed by file attributes such as
+        "Last-Modified" and "size".
+
+        For example, "smb://SERVER" returns a list of all shares on the given
+        SMB/CIFS server; "nfs://servername/path" obtains a directory listing
+        from the NFS server.
+
+    .. versionadded:: MPD protocol 0.19
+    """
+    raise exceptions.MpdNotImplemented  # TODO
+
+
 @protocol.commands.add('lsinfo')
 def lsinfo(context, uri=None):
     """

tests/mpd/protocol/test_music_db.py

@@ -295,6 +295,10 @@ class MusicDatabaseHandlerTest(protocol.BaseTestCase):
         self.assertInResponse('directory: /dummy/a')
         self.assertInResponse('directory: /dummy/a [2]')
 
+    def test_listfiles(self):
+        self.send_request('listfiles')
+        self.assertEqualResponse('ACK [0@0] {listfiles} Not implemented')
+
     def test_lsinfo_without_path_returns_same_as_for_root(self):
         last_modified = 1390942873222
         self.backend.playlists.set_dummy_playlists([