API: finish LocationEvent.lastevent removal

tacaswell · tacaswell · commit 91a67d9e4cfc · 2023-10-27T16:28:55.000-04:00
diff --git a/doc/api/next_api_changes/removals/000-TAC.rst b/doc/api/next_api_changes/removals/000-TAC.rst
@@ -0,0 +1,7 @@
+Remove hard reference to ``lastevent`` in ``LocationEvent``
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+
+This was previously used to detect exiting from axes, however the hard
+reference would keep closed `Figure` objects and their children alive longer
+than expected.
diff --git a/lib/matplotlib/backend_bases.py b/lib/matplotlib/backend_bases.py
@@ -1339,10 +1339,6 @@ class LocationEvent(Event):
         The keyboard modifiers currently being pressed (except for KeyEvent).
     """
 
-    # Fully delete all occurrences of lastevent after deprecation elapses.
-    _lastevent = None
-    lastevent = _api.deprecated("3.8")(
-        _api.classproperty(lambda cls: cls._lastevent))
     _last_axes_ref = None
 
     def __init__(self, name, canvas, x, y, guiEvent=None, *, modifiers=None):
@@ -1595,8 +1591,6 @@ def _mouse_handler(event):
                 event.canvas.callbacks.process("axes_enter_event", event)
         LocationEvent._last_axes_ref = (
             weakref.ref(event.inaxes) if event.inaxes else None)
-        LocationEvent._lastevent = (
-            None if event.name == "figure_leave_event" else event)
 
 
 def _get_renderer(figure, print_method=None):
