Temp changes for profiling

app/playlistmodel.py

@@ -92,7 +92,7 @@ class PlaylistModel(QAbstractTableModel):
             # Ensure row numbers in playlist are contiguous
             PlaylistRows.fixup_rownumbers(session, playlist_id)
             # Populate self.playlist_rows
-            self.refresh_data(session)
+            self.load_data(session)
         self.update_track_times()
 
     def __repr__(self) -> str:
@@ -803,8 +803,10 @@ class PlaylistModel(QAbstractTableModel):
         self.update_track_times()
         self.invalidate_rows(list(row_map.keys()))
 
+    @line_profiler.profile
     def move_rows_between_playlists(
-        self, from_rows: list[int], to_row_number: int, to_playlist_id: int
+        self, from_rows: list[int], to_row_number: int, to_playlist_id: int,
+        dummy_for_profiling=None
     ) -> None:
         """
         Move the playlist rows given to to_row and below of to_playlist.
@@ -1002,6 +1004,33 @@ class PlaylistModel(QAbstractTableModel):
         # Copy to self.playlist_rows
         self.playlist_rows = new_playlist_rows
 
+    # Same as refresh data, but only used when creating playslit.
+    # Distinguishes profile time between initial load and other
+    # refreshes.
+    def load_data(self, session: db.session, dummy_for_profiling=None) -> None:
+        """Populate self.playlist_rows with playlist data"""
+
+        # We used to clear self.playlist_rows each time but that's
+        # expensive and slow on big playlists
+
+        # Note where each playlist_id is
+        plid_to_row: dict[int, int] = {}
+        for oldrow in self.playlist_rows:
+            plrdata = self.playlist_rows[oldrow]
+            plid_to_row[plrdata.playlistrow_id] = plrdata.row_number
+
+        # build a new playlist_rows
+        new_playlist_rows: dict[int, RowAndTrack] = {}
+        for p in PlaylistRows.get_playlist_rows(session, self.playlist_id):
+            if p.id not in plid_to_row:
+                new_playlist_rows[p.row_number] = RowAndTrack(p)
+            else:
+                new_playlist_rows[p.row_number] = self.playlist_rows[plid_to_row[p.id]]
+                new_playlist_rows[p.row_number].row_number = p.row_number
+
+        # Copy to self.playlist_rows
+        self.playlist_rows = new_playlist_rows
+
     def refresh_row(self, session, row_number):
         """Populate dict for one row from database"""