curds: Send next-track notification when changing tracks

This lets the UI know that something changed so scrolling can happen in
the UI.

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

curds/playlist/root.py

@@ -6,6 +6,7 @@ from . import genre
 from . import library
 from . import node
 from . import previous
+from .. import notify
 import random
 
 
@@ -38,6 +39,7 @@ class PlaylistRoot(node.PlaylistNode):
 
         self.lookup("Previous").add(self.track)
         self.current_changed(old)
+        notify.notify("next-track", self.track)
         return self.track
 
     def peek(self, n):

curds/playlist/test_root.py

@@ -23,6 +23,7 @@ class TestPlaylistRoot(unittest.TestCase):
         tags.clear()
         library.reset()
         notify.register("new-playlist",     self.on_new_playlist)
+        notify.register("next-track",       self.on_next_track)
         notify.register("playlist-changed", self.on_playlist_changed)
 
         try:
@@ -32,12 +33,14 @@ class TestPlaylistRoot(unittest.TestCase):
         self.cb_plist  = None
         self.cb_index  = None
         self.cb_first  = None
+        self.cb_track  = None
         self.cb_change = [ ]
 
     def tearDown(self):
         notify.cancel("new-track", self.playman.lookup("Collection").add)
         notify.cancel("new-track", self.playman.lookup("Genres").new_track)
         notify.cancel("new-playlist", self.on_new_playlist)
+        notify.cancel("next-track",   self.on_next_track)
         notify.register("playlist-changed", self.on_playlist_changed)
         library.stop()
 
@@ -49,6 +52,9 @@ class TestPlaylistRoot(unittest.TestCase):
     def on_playlist_changed(self, plist):
         self.cb_change.append(plist)
 
+    def on_next_track(self, track):
+        self.cb_track = track
+
     def test_root_init(self):
         self.assertIsInstance(self.playman, root.PlaylistRoot)
         self.assertIsInstance(self.playman, node.PlaylistNode)
@@ -99,6 +105,7 @@ class TestPlaylistRoot(unittest.TestCase):
         self.assertEqual(self.playman.track, track1)
         self.assertEqual(clist.current, 0)
         self.assertEqual(track1,  clist[0])
+        self.assertEqual(self.cb_track, track1)
 
         self.assertEqual(len(prev), 1)
         self.assertEqual(prev[0], track1)
@@ -107,12 +114,14 @@ class TestPlaylistRoot(unittest.TestCase):
         self.assertEqual(self.playman.track, track2)
         self.assertEqual(clist.current, 1)
         self.assertEqual(track2,  clist[1])
+        self.assertEqual(self.cb_track, track2)
 
         self.assertEqual(len(prev), 2)
         self.assertEqual(prev[0], track2)
         self.assertEqual(prev[1], track1)
 
         self.assertEqual(self.playman.previous(), track1)
+        self.assertEqual(self.cb_track, track2)
 
         self.playman.reset()
         self.assertEqual(len(self.playman.lookup("Previous")), 0)