curds: Pop empty playlists earlier during playlist.next()

Rather than waiting until the next next() call, we can detect and remove
them right away.

Signed-off-by: Anna Schumaker <Anna@NoWheyCreamery.com>

curds/playlist/__init__.py

@@ -27,13 +27,19 @@ def lookup(name):
 def next():
     global Track
     with Lock:
-        Track = Current[0].next()
+        orig  = Current[0]
+        Track = orig.next()
 
         while Track == None and len(Current) > 1:
-            Current.pop(0).changed()
-            Current[0].changed()
+            Current.pop(0)
             Track = Current[0].next()
 
+        if len(Current[0]) == 0 and len(Current) > 1:
+            Current.pop(0)
+        if orig != Current[0]:
+            orig.changed()
+            Current[0].changed()
+
         Root.lookup("Previous").add(Track)
         return Track
 

curds/test_playlist.py

@@ -61,7 +61,7 @@ class TestPlaylist(unittest.TestCase):
 
         track1 = playlist.next()
         self.assertEqual(playlist.Track, track1)
-        self.assertEqual(playlist.Current, [ upnxt, clist ])
+        self.assertEqual(playlist.Current, [ clist ])
 
         self.assertEqual(len(prev), 1)
         self.assertEqual(prev[0], track1)