db: Give playlist tables a refilter() function

This is used to notify the model that the rows have changed when it's
not automatically being detected. I first noticed this when attempting
to disable incremental filtering, due to the Artist list not getting
refiltered when new child Albums were added to the Artist.

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

emmental/db/playlist.py

@@ -69,6 +69,8 @@ class Playlist(table.Row):
     def add_child(self, child: typing.Self) -> None:
         """Add a child Playlist to this Playlist."""
         self.child_set.add_row(child)
+        if self.child_set.keyset.n_keys == 1:
+            self.table.refilter(Gtk.FilterChange.LESS_STRICT)
 
     def add_track(self, track: Track, *, idle: bool = False) -> None:
         """Add a Track to this Playlist."""
@@ -110,6 +112,8 @@ class Playlist(table.Row):
     def remove_child(self, child: typing.Self) -> None:
         """Remove a child Playlist from this Playlist."""
         self.child_set.remove_row(child)
+        if self.child_set.keyset.n_keys == 0:
+            self.table.refilter(Gtk.FilterChange.MORE_STRICT)
 
     def remove_track(self, track: table.Row, *, idle: bool = False) -> None:
         """Remove a Track from this Playlist."""
@@ -154,6 +158,10 @@ class Table(table.Table):
     def __create_tree(self, plist: Playlist) -> Gtk.FilterListModel | None:
         return plist.children
 
+    def __refilter(self, change_how: Gtk.FilterChange) -> bool:
+        self.get_filter().changed(change_how)
+        return True
+
     def do_add_track(self, playlist: Playlist, track: Track) -> bool:
         """Add a Track to the Playlist."""
         raise NotImplementedError
@@ -255,6 +263,11 @@ class Table(table.Table):
                 playlist.sort_order = "user"
         return res
 
+    def refilter(self, change_how: Gtk.FilterChange) -> None:
+        """Schedule refiltering the Table."""
+        self.queue.cancel_task(self.__refilter)
+        self.queue.push(self.__refilter, change_how, first=True)
+
     def remove_system_track(self, playlist: Playlist, track: Track) -> bool:
         """Remove a Track from a system Playlist."""
         return self.sql("""DELETE FROM system_tracks

tests/db/test_playlist.py

@@ -21,6 +21,7 @@ class TestPlaylistRow(unittest.TestCase):
         self.table.move_track_up = unittest.mock.Mock(return_value=True)
         self.table.get_trackids = unittest.mock.Mock(return_value={1, 2, 3})
         self.table.get_track_order = unittest.mock.Mock()
+        self.table.refilter = unittest.mock.Mock()
         self.table.queue = emmental.db.idle.Queue()
         self.table.update = unittest.mock.Mock(return_value=True)
 
@@ -114,11 +115,16 @@ class TestPlaylistRow(unittest.TestCase):
     def test_add_child(self):
         """Test adding a child playlist to the playlist."""
         table = emmental.db.table.Table(None)
-        child = tests.util.table.MockRow(table=table, number=1)
+        child1 = tests.util.table.MockRow(table=table, number=1)
+        child2 = tests.util.table.MockRow(table=table, number=2)
         self.playlist.add_children(table, set())
 
-        self.playlist.add_child(child)
-        self.assertIn(child, self.playlist.child_set)
+        self.playlist.add_child(child1)
+        self.assertIn(child1, self.playlist.child_set)
+        self.table.refilter.assert_called_with(Gtk.FilterChange.LESS_STRICT)
+
+        self.playlist.add_child(child2)
+        self.table.refilter.assert_called_once()
 
     def test_add_track(self):
         """Test adding a track to the playlist."""
@@ -179,12 +185,19 @@ class TestPlaylistRow(unittest.TestCase):
     def test_remove_child(self):
         """Test removing a child playlist from the playlist."""
         table = emmental.db.table.Table(None)
-        child = tests.util.table.MockRow(table=table, number=1)
+        child1 = tests.util.table.MockRow(table=table, number=1)
+        child2 = tests.util.table.MockRow(table=table, number=2)
         self.playlist.add_children(table, set())
+        self.playlist.add_child(child1)
+        self.playlist.add_child(child2)
+        self.table.refilter.reset_mock()
 
-        self.playlist.add_child(child)
-        self.playlist.remove_child(child)
-        self.assertFalse(child in self.playlist.child_set)
+        self.playlist.remove_child(child1)
+        self.assertFalse(child1 in self.playlist.child_set)
+        self.table.refilter.assert_not_called()
+
+        self.playlist.remove_child(child2)
+        self.table.refilter.assert_called_with(Gtk.FilterChange.MORE_STRICT)
 
     def test_remove_track(self):
         """Test removing a track from the playlist."""
@@ -403,6 +416,27 @@ class TestPlaylistTable(tests.util.TestCase):
         self.table.move_track_up(plist, self.track)
         self.assertEqual(plist.sort_order, "user")
 
+    def test_refilter(self):
+        """Test refiltering the playlist table."""
+        self.table.queue.push(unittest.mock.Mock())
+
+        with unittest.mock.patch.object(self.table.get_filter(),
+                                        "changed") as mock_changed:
+            self.table.refilter(Gtk.FilterChange.MORE_STRICT)
+            self.assertEqual(self.table.queue[0],
+                             (self.table._Table__refilter,
+                              Gtk.FilterChange.MORE_STRICT))
+            mock_changed.assert_not_called()
+
+            self.table.refilter(Gtk.FilterChange.LESS_STRICT)
+            self.assertEqual(self.table.queue[0],
+                             (self.table._Table__refilter,
+                              Gtk.FilterChange.LESS_STRICT))
+            mock_changed.assert_not_called()
+
+            self.table.queue.complete()
+            mock_changed.assert_called_with(Gtk.FilterChange.LESS_STRICT)
+
     def test_remove_track(self):
         """Test adding a track to a playlist."""
         self.assertTrue(self.table.system_tracks)