Merge f1a97218a8 into 7e3df43463

qutebrowser/app.py

@@ -413,10 +413,8 @@ def on_focus_changed(_old, new):
 
     window = new.window()
     if isinstance(window, mainwindow.MainWindow):
-        objreg.register('last-focused-main-window', window, update=True)
-        # A focused window must also be visible, and in this case we should
-        # consider it as the most recently looked-at window
-        objreg.register('last-visible-main-window', window, update=True)
+        objreg.window_visibility_history.append(window)
+        objreg.window_focus_history.append(window)
 
 
 def open_desktopservices_url(url):

qutebrowser/mainwindow/mainwindow.py

@@ -623,13 +623,22 @@ class MainWindow(QWidget):
         self.tabbed_browser.widget.tab_bar().refresh()
 
     def showEvent(self, e):
-        """Extend showEvent to register us as the last-visible-main-window.
+        """Extend showEvent to update window-visibility-history.
 
         Args:
             e: The QShowEvent
         """
         super().showEvent(e)
-        objreg.register('last-visible-main-window', self, update=True)
+        objreg.window_visibility_history.append(self)
+
+    def hideEvent(self, e):
+        """Extend hideEvent to update window-visibility-history.
+
+        Args:
+            e: The QHideEvent
+        """
+        super().hideEvent(e)
+        objreg.window_visibility_history.remove(self)
 
     def _confirm_quit(self):
         """Confirm that this window should be closed.
@@ -689,13 +698,8 @@ class MainWindow(QWidget):
 
         e.accept()
 
-        for key in ['last-visible-main-window', 'last-focused-main-window']:
-            try:
-                win = objreg.get(key)
-                if self is win:
-                    objreg.delete(key)
-            except KeyError:
-                pass
+        objreg.window_focus_history.remove(self)
+        objreg.window_visibility_history.remove(self)
 
         sessions.session_manager.save_last_window_session()
         self._save_geometry()

qutebrowser/utils/objreg.py

@@ -7,6 +7,7 @@
 
 import collections
 import functools
+import weakref
 from typing import (TYPE_CHECKING, Any,
                     Optional, Union)
 from collections.abc import MutableMapping, MutableSequence, Sequence, Callable
@@ -38,6 +39,48 @@ class CommandOnlyError(Exception):
     """Raised when an object is requested which is used for commands only."""
 
 
+_WindowRefType = weakref.ReferenceType['mainwindow.MainWindow']
+
+
+class WindowAccessHistory():
+    """Contains an ordered list of windows, sorted by last added.
+
+    Uses weak references to avoid memory leaks.
+    """
+
+    def __init__(self) -> None:
+        self._windows: list[_WindowRefType] = []
+
+    def append(self, window: 'mainwindow.MainWindow') -> None:
+        """Append a window to the access history."""
+        self.remove(window)
+        self._windows.append(weakref.ref(window))
+
+    def remove(self, window: 'mainwindow.MainWindow') -> None:
+        """Remove a window from the access history."""
+        try:
+            self._windows.remove(weakref.ref(window))
+        except ValueError:
+            pass
+
+    def last(self) -> Optional['mainwindow.MainWindow']:
+        """Return the last window from the access history.
+
+        Prune any None values and windows that are shutting down and
+        return the last still existing window from the list.
+        """
+        for ref in reversed(self._windows):
+            win = ref()
+            if win is None or win.tabbed_browser.is_shutting_down:
+                self._windows.pop()
+            else:
+                return win
+        return None
+
+
+window_visibility_history = WindowAccessHistory()
+window_focus_history = WindowAccessHistory()
+
 _IndexType = Union[str, int]
 
 
@@ -308,24 +351,12 @@ def dump_objects() -> Sequence[str]:
 
 def last_visible_window() -> 'mainwindow.MainWindow':
     """Get the last visible window, or the last focused window if none."""
-    try:
-        window = get('last-visible-main-window')
-    except KeyError:
-        return last_focused_window()
-    if window.tabbed_browser.is_shutting_down:
-        return last_focused_window()
-    return window
+    return window_visibility_history.last() or last_focused_window()
 
 
 def last_focused_window() -> 'mainwindow.MainWindow':
     """Get the last focused window, or the last window if none."""
-    try:
-        window = get('last-focused-main-window')
-    except KeyError:
-        return last_opened_window()
-    if window.tabbed_browser.is_shutting_down:
-        return last_opened_window()
-    return window
+    return window_focus_history.last() or last_opened_window()
 
 
 def _window_by_index(idx: int) -> 'mainwindow.MainWindow':