Fix various leaks (#1672)

* Fix wrong hook being torn down

* Fix item models not being destroyed

* Add missing gc for FilteredDeckConfigDialog

* Add missing type annotation

* Pass calling widget as parent to QTimer

Implicitly passing `self.mw` as the parent means that the QTimer won't
get destroyed before quitting the app, which also thwarts garbage
collection of any data captured by a passed closure.

* Make `Editor._links` an instance variable

Browser is inserting a closure into this dict capturing itself. As a class
variable, it won't get destroyed, so neither will the browser.

* Make `Editor._links` funcs take instance again

* Deprecate calling progress.timer() without parent

* show caller location when printing deprecation warning (dae)

qt/aqt/addons.py

@@ -1150,7 +1150,9 @@ class DownloaderInstaller(QObject):
         self.mgr.mw.progress.finish()
         # qt gets confused if on_done() opens new windows while the progress
         # modal is still cleaning up
-        self.mgr.mw.progress.timer(50, lambda: self.on_done(self.log), False)
+        self.mgr.mw.progress.timer(
+            50, lambda: self.on_done(self.log), False, parent=self
+        )
 
 
 def show_log_to_user(parent: QWidget, log: list[DownloadLogEntry]) -> None:
@@ -1404,6 +1406,7 @@ def check_for_updates(
                 lambda: update_info_received(future),
                 False,
                 requiresCollection=False,
+                parent=mgr.mw,
             )
             return
 

qt/aqt/browser/browser.py

@@ -562,7 +562,7 @@ class Browser(QMainWindow):
 
         # schedule sidebar to refresh after browser window has loaded, so the
         # UI is more responsive
-        self.mw.progress.timer(10, self.sidebar.refresh, False)
+        self.mw.progress.timer(10, self.sidebar.refresh, False, parent=self.sidebar)
 
     def showSidebar(self) -> None:
         self.sidebarDockWidget.setVisible(True)
@@ -899,7 +899,7 @@ class Browser(QMainWindow):
     def teardownHooks(self) -> None:
         gui_hooks.undo_state_did_change.remove(self.on_undo_state_change)
         gui_hooks.backend_will_block.remove(self.table.on_backend_will_block)
-        gui_hooks.backend_did_block.remove(self.table.on_backend_will_block)
+        gui_hooks.backend_did_block.remove(self.table.on_backend_did_block)
         gui_hooks.operation_did_execute.remove(self.on_operation_did_execute)
         gui_hooks.focus_did_change.remove(self.on_focus_change)
         gui_hooks.flag_label_did_change.remove(self._update_flag_labels)

qt/aqt/browser/previewer.py

@@ -106,7 +106,7 @@ class Previewer(QDialog):
 
     def _on_finished(self, ok: int) -> None:
         saveGeom(self, "preview")
-        self.mw.progress.timer(100, self._on_close, False)
+        self.mw.progress.timer(100, self._on_close, False, parent=self)
 
     def _on_replay_audio(self) -> None:
         if self._state == "question":
@@ -156,7 +156,7 @@ class Previewer(QDialog):
         delay = 300
         if elap_ms < delay:
             self._timer = self.mw.progress.timer(
-                delay - elap_ms, self._render_scheduled, False
+                delay - elap_ms, self._render_scheduled, False, parent=self
             )
         else:
             self._render_scheduled()

qt/aqt/browser/sidebar/model.py

@@ -15,7 +15,7 @@ class SidebarModel(QAbstractItemModel):
     def __init__(
         self, sidebar: aqt.browser.sidebar.SidebarTreeView, root: SidebarItem
     ) -> None:
-        super().__init__()
+        super().__init__(sidebar)
         self.sidebar = sidebar
         self.root = root
         self._cache_rows(root)

qt/aqt/browser/sidebar/tree.py

@@ -177,6 +177,8 @@ class SidebarTreeView(QTreeView):
             # block repainting during refreshing to avoid flickering
             self.setUpdatesEnabled(False)
 
+            if old_model := self.model():
+                old_model.deleteLater()
             model = SidebarModel(self, root)
             self.setModel(model)
 

qt/aqt/browser/table/model.py

@@ -34,12 +34,13 @@ class DataModel(QAbstractTableModel):
 
     def __init__(
         self,
+        parent: QObject,
         col: Collection,
         state: ItemState,
         row_state_will_change_callback: Callable,
         row_state_changed_callback: Callable,
     ) -> None:
-        QAbstractTableModel.__init__(self)
+        super().__init__(parent)
         self.col: Collection = col
         self.columns: dict[str, Column] = {
             c.key: c for c in self.col.all_browser_columns()

qt/aqt/browser/table/table.py

@@ -40,6 +40,7 @@ class Table:
             else CardState(self.col)
         )
         self._model = DataModel(
+            self.browser,
             self.col,
             self._state,
             self._on_row_state_will_change,

qt/aqt/clayout.py

@@ -499,7 +499,9 @@ class CardLayout(QDialog):
     def renderPreview(self) -> None:
         # schedule a preview when timing stops
         self.cancelPreviewTimer()
-        self._previewTimer = self.mw.progress.timer(200, self._renderPreview, False)
+        self._previewTimer = self.mw.progress.timer(
+            200, self._renderPreview, False, parent=self
+        )
 
     def cancelPreviewTimer(self) -> None:
         if self._previewTimer:

qt/aqt/editor.py

@@ -123,6 +123,7 @@ class Editor:
         self.last_field_index: int | None = None
         # current card, for card layout
         self.card: Card | None = None
+        self._init_links()
         self.setupOuter()
         self.setupWeb()
         self.setupShortcuts()
@@ -394,7 +395,9 @@ require("anki/ui").loaded.then(() => require("anki/NoteEditor").instances[0].too
                 if gui_hooks.editor_did_unfocus_field(False, self.note, ord):
                     # something updated the note; update it after a subsequent focus
                     # event has had time to fire
-                    self.mw.progress.timer(100, self.loadNoteKeepingFocus, False)
+                    self.mw.progress.timer(
+                        100, self.loadNoteKeepingFocus, False, parent=self.widget
+                    )
                 else:
                     self._check_and_update_duplicate_display_async()
             else:
@@ -549,7 +552,7 @@ require("anki/ui").loaded.then(() => require("anki/NoteEditor").instances[0].too
         "Save unsaved edits then call callback()."
         if not self.note:
             # calling code may not expect the callback to fire immediately
-            self.mw.progress.timer(10, callback, False)
+            self.mw.progress.timer(10, callback, False, parent=self.widget)
             return
         self.web.evalWithCallback("saveNow(%d)" % keepFocus, lambda res: callback())
 
@@ -1104,29 +1107,30 @@ require("anki/ui").loaded.then(() => require("anki/NoteEditor").instances[0].too
     # Links from HTML
     ######################################################################
 
-    _links: dict[str, Callable] = dict(
+    def _init_links(self) -> None:
-        fields=onFields,
+        self._links: dict[str, Callable] = dict(
-        cards=onCardLayout,
+            fields=Editor.onFields,
-        bold=toggleBold,
+            cards=Editor.onCardLayout,
-        italic=toggleItalic,
+            bold=Editor.toggleBold,
-        underline=toggleUnderline,
+            italic=Editor.toggleItalic,
-        super=toggleSuper,
+            underline=Editor.toggleUnderline,
-        sub=toggleSub,
+            super=Editor.toggleSuper,
-        clear=removeFormat,
+            sub=Editor.toggleSub,
-        colour=onForeground,
+            clear=Editor.removeFormat,
-        changeCol=onChangeCol,
+            colour=Editor.onForeground,
-        cloze=onCloze,
+            changeCol=Editor.onChangeCol,
-        attach=onAddMedia,
+            cloze=Editor.onCloze,
-        record=onRecSound,
+            attach=Editor.onAddMedia,
-        more=onAdvanced,
+            record=Editor.onRecSound,
-        dupes=showDupes,
+            more=Editor.onAdvanced,
-        paste=onPaste,
+            dupes=Editor.showDupes,
-        cutOrCopy=onCutOrCopy,
+            paste=Editor.onPaste,
-        htmlEdit=onHtmlEdit,
+            cutOrCopy=Editor.onCutOrCopy,
-        mathjaxInline=insertMathjaxInline,
+            htmlEdit=Editor.onHtmlEdit,
-        mathjaxBlock=insertMathjaxBlock,
+            mathjaxInline=Editor.insertMathjaxInline,
-        mathjaxChemistry=insertMathjaxChemistry,
+            mathjaxBlock=Editor.insertMathjaxBlock,
-    )
+            mathjaxChemistry=Editor.insertMathjaxChemistry,
+        )
 
 
 # Pasting, drag & drop, and keyboard layouts

qt/aqt/filtered_deck.py

@@ -50,6 +50,7 @@ class FilteredDeckConfigDialog(QDialog):
 
         QDialog.__init__(self, mw)
         self.mw = mw
+        mw.garbage_collect_on_dialog_finish(self)
         self.col = self.mw.col
         self._desired_search_1 = search
         self._desired_search_2 = search_2

qt/aqt/main.py

@@ -187,7 +187,9 @@ class AnkiQt(QMainWindow):
             fn()
             gui_hooks.main_window_did_init()
 
-        self.progress.timer(10, on_window_init, False, requiresCollection=False)
+        self.progress.timer(
+            10, on_window_init, False, requiresCollection=False, parent=self
+        )
 
     def setupUI(self) -> None:
         self.col = None
@@ -226,6 +228,7 @@ class AnkiQt(QMainWindow):
                     self.setupProfileAfterWebviewsLoaded,
                     False,
                     requiresCollection=False,
+                    parent=self,
                 )
                 return
             else:
@@ -911,7 +914,7 @@ title="{}" {}>{}</button>""".format(
             self.col.db.rollback()
             self.close()
 
-        self.progress.timer(100, quit, False)
+        self.progress.timer(100, quit, False, parent=self)
 
     def setupProgress(self) -> None:
         self.progress = aqt.progress.ProgressManager(self)
@@ -1062,6 +1065,7 @@ title="{}" {}>{}</button>""".format(
             theme_manager.apply_style_if_system_style_changed,
             True,
             False,
+            parent=self,
         )
 
     def set_theme(self, theme: Theme) -> None:
@@ -1354,14 +1358,16 @@ title="{}" {}>{}</button>""".format(
 
     def setup_timers(self) -> None:
         # refresh decks every 10 minutes
-        self.progress.timer(10 * 60 * 1000, self.onRefreshTimer, True)
+        self.progress.timer(10 * 60 * 1000, self.onRefreshTimer, True, parent=self)
         # check media sync every 5 minutes
-        self.progress.timer(5 * 60 * 1000, self.on_autosync_timer, True)
+        self.progress.timer(5 * 60 * 1000, self.on_autosync_timer, True, parent=self)
         # periodic garbage collection
-        self.progress.timer(15 * 60 * 1000, self.garbage_collect_now, False)
+        self.progress.timer(
+            15 * 60 * 1000, self.garbage_collect_now, False, parent=self
+        )
         # ensure Python interpreter runs at least once per second, so that
         # SIGINT/SIGTERM is processed without a long delay
-        self.progress.timer(1000, lambda: None, True, False)
+        self.progress.timer(1000, lambda: None, True, False, parent=self)
 
     def onRefreshTimer(self) -> None:
         if self.state == "deckBrowser":
@@ -1690,7 +1696,11 @@ title="{}" {}>{}</button>""".format(
         if self.state == "startup":
             # try again in a second
             self.progress.timer(
-                1000, lambda: self.onAppMsg(buf), False, requiresCollection=False
+                1000,
+                lambda: self.onAppMsg(buf),
+                False,
+                requiresCollection=False,
+                parent=self,
             )
             return
         elif self.state == "profileManager":
@@ -1757,7 +1767,7 @@ title="{}" {}>{}</button>""".format(
     def deferred_delete_and_garbage_collect(self, obj: QObject) -> None:
         obj.deleteLater()
         self.progress.timer(
-            1000, self.garbage_collect_now, False, requiresCollection=False
+            1000, self.garbage_collect_now, False, requiresCollection=False, parent=self
         )
 
     def disable_automatic_garbage_collection(self) -> None:

qt/aqt/progress.py

@@ -5,6 +5,7 @@ from __future__ import annotations
 import time
 
 import aqt.forms
+from anki._legacy import print_deprecation_warning
 from aqt.qt import *
 from aqt.utils import disable_help_button, tr
 
@@ -29,7 +30,13 @@ class ProgressManager:
     # (likely due to some long-running DB operation)
 
     def timer(
-        self, ms: int, func: Callable, repeat: bool, requiresCollection: bool = True
+        self,
+        ms: int,
+        func: Callable,
+        repeat: bool,
+        requiresCollection: bool = True,
+        *,
+        parent: QObject = None,
     ) -> QTimer:
         """Create and start a standard Anki timer.
 
@@ -42,6 +49,12 @@ class ProgressManager:
         timer to fire even when there is no collection, but will still
         only fire when there is no current progress dialog."""
 
+        if parent is None:
+            print_deprecation_warning(
+                "to avoid memory leaks, pass an appropriate parent to progress.timer()"
+            )
+            parent = self.mw
+
         def handler() -> None:
             if requiresCollection and not self.mw.col:
                 # no current collection; timer is no longer valid
@@ -59,7 +72,7 @@ class ProgressManager:
                     # retry in 100ms
                     self.timer(100, func, False, requiresCollection)
 
-        t = QTimer(self.mw)
+        t = QTimer(parent)
         if not repeat:
             t.setSingleShot(True)
         qconnect(t.timeout, handler)

qt/aqt/utils.py

@@ -537,7 +537,9 @@ def ensureWidgetInScreenBoundaries(widget: QWidget) -> None:
     handle = widget.window().windowHandle()
     if not handle:
         # window has not yet been shown, retry later
-        aqt.mw.progress.timer(50, lambda: ensureWidgetInScreenBoundaries(widget), False)
+        aqt.mw.progress.timer(
+            50, lambda: ensureWidgetInScreenBoundaries(widget), False, parent=widget
+        )
         return
 
     # ensure widget is smaller than screen bounds
@@ -745,7 +747,7 @@ def tooltip(
     lab.move(aw.mapToGlobal(QPoint(0 + x_offset, aw.height() - y_offset)))
     lab.show()
     _tooltipTimer = aqt.mw.progress.timer(
-        period, closeTooltip, False, requiresCollection=False
+        period, closeTooltip, False, requiresCollection=False, parent=aw
     )
     _tooltipLabel = lab
 

qt/aqt/webview.py

@@ -628,7 +628,7 @@ html {{ {font} }}
 
         if qvar is None:
 
-            mw.progress.timer(1000, mw.reset, False)
+            mw.progress.timer(1000, mw.reset, False, parent=self)
             return
 
         self.setFixedHeight(int(qvar))