cleanup tests and code

- move tests to tests/frontends/mpd/stored_playlists_test.py

stored_playlists_test.py:
- rename test methods names to remove _config
- remove unnecessary imports, setup, teardown, variables
- sort remaining imports

mopidy/frontends/mpd/dispatcher.py:
- remove regex comment

mopidy/frontends/mpd/dispatcher.py

@@ -236,7 +236,6 @@ class MpdContext(object):
     #: The subsytems that we want to be notified about in idle mode.
     subscriptions = None
 
-    #regex for invalid characters in playlist names
     _invalid_playlist_chars = re.compile(r'[\n\r/]')
 
     def __init__(self, dispatcher, session=None, config=None, core=None):

tests/frontends/mpd/dispatcher_test.py

@@ -6,7 +6,7 @@ import pykka
 
 from mopidy import core
 from mopidy.backends import dummy
-from mopidy.frontends.mpd.dispatcher import MpdDispatcher, MpdContext
+from mopidy.frontends.mpd.dispatcher import MpdDispatcher
 from mopidy.frontends.mpd.exceptions import MpdAckError
 from mopidy.frontends.mpd.protocol import request_handlers, handle_request
 
@@ -63,31 +63,3 @@ class MpdDispatcherTest(unittest.TestCase):
         result = self.dispatcher.handle_request('known request')
         self.assertIn('OK', result)
         self.assertIn(expected, result)
-
-
-class MpdContextTest(unittest.TestCase):
-    def setUp(self):
-        config = {
-            'mpd': {
-                'password': None,
-            }
-        }
-        self.backend = dummy.create_dummy_backend_proxy()
-        self.core = core.Core.start(backends=[self.backend]).proxy()
-        self.dispatcher = MpdDispatcher(config=config)
-        self.context = self.dispatcher.context
-
-    def tearDown(self):
-        pykka.ActorRegistry.stop_all()
-
-    def test_context_create_unique_name_replaces_newlines_with_space(self):
-        result = self.context.create_unique_name("playlist name\n")
-        self.assertEqual("playlist name ", result)
-
-    def test_context_create_unique_name_replaces_carriage_returns_with_space(self):
-        result = self.context.create_unique_name("playlist name\r")
-        self.assertEqual("playlist name ", result)
-
-    def test_context_create_unique_name_replaces_forward_slashes_with_space(self):
-        result = self.context.create_unique_name("playlist name/")
-        self.assertEqual("playlist name ", result)

tests/frontends/mpd/stored_playlists_test.py

@@ -0,0 +1,28 @@
+from __future__ import unicode_literals
+
+import unittest
+
+from mopidy.frontends.mpd.dispatcher import MpdContext, MpdDispatcher
+
+
+class MpdContextTest(unittest.TestCase):
+    def setUp(self):
+        config = {
+            'mpd': {
+                'password': None,
+            }
+        }
+        dispatcher = MpdDispatcher(config=config)
+        self.context = dispatcher.context
+
+    def test_create_unique_name_replaces_newlines_with_space(self):
+        result = self.context.create_unique_name("playlist name\n")
+        self.assertEqual("playlist name ", result)
+
+    def test_create_unique_name_replaces_carriage_returns_with_space(self):
+        result = self.context.create_unique_name("playlist name\r")
+        self.assertEqual("playlist name ", result)
+
+    def test_create_unique_name_replaces_forward_slashes_with_space(self):
+        result = self.context.create_unique_name("playlist name/")
+        self.assertEqual("playlist name ", result)