gui: fix memory leak in SongMinicardListModel (#822)

feeluown/gui/components/player_playlist.py

@@ -11,7 +11,9 @@
 
 
 class PlayerPlaylistModel(SongMiniCardListModel):
- # FIXME: make this singleton
+ """
+ this is a singleton class (ensured by PlayerPlaylistView)
+ """
 
  def __init__(self, playlist, *args, **kwargs):
  reader = create_reader(playlist.list())
@@ -47,17 +49,19 @@ def on_songs_removed(self, index, count):
 
 class PlayerPlaylistView(SongMiniCardListView):
 
+ _model = None
+
  def __init__(self, app, *args, **kwargs):
  super().__init__(*args, **kwargs)
  self._app = app
 
  self.play_song_needed.connect(self._app.playlist.play_model)
- self.setModel(
- PlayerPlaylistModel(
+ if PlayerPlaylistView._model is None:
+ PlayerPlaylistView._model = PlayerPlaylistModel(
  self._app.playlist,
  fetch_cover_wrapper(self._app),
  )
- )
+ self.setModel(PlayerPlaylistView._model)
 
  def contextMenuEvent(self, e):
  index = self.indexAt(e.pos())

feeluown/gui/widgets/song_minicard_list.py

@@ -31,6 +31,7 @@ def __init__(self, fetch_image, parent=None):
  self._items = []
  self.fetch_image = fetch_image
  self.pixmaps = {} # {uri: (Option<pixmap>, Option<color>)}
+ self.rowsAboutToBeRemoved.connect(self.on_rows_about_to_be_removed)
 
  def rowCount(self, _=QModelIndex()):
  return len(self._items)
@@ -45,7 +46,7 @@ def _fetch_image_callback(self, item):
  # TODO: duplicate code with ImgListModel
  def cb(content):
  uri = reverse(item)
- if content is None:
+ if content is None and uri in self.pixmaps:
  self.pixmaps[uri] = (self.pixmaps[uri][1], None)
  return
 
@@ -87,8 +88,15 @@ def data(self, index, role=Qt.DisplayRole):
  return (song, pixmap)
  return None
 
+ def on_rows_about_to_be_removed(self, _, first, last):
+ for i in range(first, last+1):
+ item = self._items[i]
+ uri = reverse(item)
+ # clear pixmap cache
+ self.pixmaps.pop(uri, None)
+
 
-class SongMiniCardListModel(BaseSongMiniCardListModel, ReaderFetchMoreMixin):
+class SongMiniCardListModel(ReaderFetchMoreMixin, BaseSongMiniCardListModel):
  def __init__(self, reader, fetch_image, parent=None):
  super().__init__(fetch_image, parent)
 

tests/gui/widgets/test_song_minicard_list.py

@@ -0,0 +1,24 @@
+import pytest
+from PyQt5.QtCore import QModelIndex
+
+from feeluown.utils import aio
+from feeluown.utils.reader import create_reader
+from feeluown.gui.widgets.song_minicard_list import SongMiniCardListModel
+
+
+@pytest.mark.asyncio
+async def test_song_mini_card_list_model_remove_pixmap(qtbot, song):
+ async def fetch_cover(*_): return b'image content'
+ model = SongMiniCardListModel(create_reader([song]), fetch_cover)
+ assert model.rowCount() == 0
+ model.fetchMore(QModelIndex())
+ await aio.sleep(0.1)
+ assert model.rowCount() == 1
+ model.get_pixmap_unblocking(song)
+ await aio.sleep(0.1)
+ assert len(model.pixmaps) == 1
+ with qtbot.waitSignal(model.rowsAboutToBeRemoved):
+ model.beginRemoveRows(QModelIndex(), 0, 0)
+ model._items.pop(0)
+ model.endRemoveRows()
+ assert len(model.pixmaps) == 0