Improve logging of test for panel destruction (PR #12291)

* Reduces the log noise during destruction of SettingsDialogs
* Makes the log easier to follow, objects and constants are now more clearly described.
* Fixes a space in the import statement, this was a typo and is strange style.

source/_UIAHandler.py

@@ -37,7 +37,7 @@
 import UIAUtils
 from comInterfaces import UIAutomationClient as UIA
 # F403: unable to detect undefined names
-from comInterfaces .UIAutomationClient import *  # noqa:  F403
+from comInterfaces.UIAutomationClient import *  # noqa:  F403
 import textInfos
 from typing import Dict
 from queue import Queue

source/gui/__init__.py

@@ -5,6 +5,7 @@
 # This file is covered by the GNU General Public License.
 # See the file COPYING for more details.
 
+import typing
 import time
 import os
 import sys
@@ -24,6 +25,7 @@
 import queueHandler
 import core
 from . import guiHelper
+from . import settingsDialogs
 from .settingsDialogs import *
 from .inputGestures import InputGesturesDialog
 import speechDictHandler
@@ -585,10 +587,16 @@ def terminate():
 	import brailleViewer
 	brailleViewer.destroyBrailleViewer()
 
-	for instance, state in gui.SettingsDialog._instances.items():
-		if state is gui.SettingsDialog._DIALOG_DESTROYED_STATE:
+	# prevent race condition with object deletion
+	# prevent deletion of the object while we work on it.
+	_SettingsDialog = settingsDialogs.SettingsDialog
+	nonWeak: typing.Dict[_SettingsDialog, _SettingsDialog] = dict(_SettingsDialog._instances)
+
+	for instance, state in nonWeak.items():
+		if state is _SettingsDialog.DialogState.DESTROYED:
 			log.error(
-				"Destroyed but not deleted instance of settings dialog exists: {!r}".format(instance)
+				"Destroyed but not deleted instance of gui.SettingsDialog exists"
+				f": {instance.title} - {instance.__class__.__qualname__} - {instance}"
 			)
 		else:
 			log.debug("Exiting NVDA with an open settings dialog: {!r}".format(instance))

source/gui/settingsDialogs.py

@@ -9,7 +9,9 @@
 from abc import ABCMeta, abstractmethod
 import copy
 import os
+from enum import IntEnum
 
+import typing
 import wx
 from vision.providerBase import VisionEnhancementProviderSettings
 from wx.lib import scrolledpanel
@@ -80,10 +82,12 @@ class SettingsDialog(
 
 	class MultiInstanceError(RuntimeError): pass
 
-	_DIALOG_CREATED_STATE = 0
-	_DIALOG_DESTROYED_STATE = 1
+	class DialogState(IntEnum):
+		CREATED = 0
+		DESTROYED = 1
+
 	# holds instances of SettingsDialogs as keys, and state as the value
-	_instances=weakref.WeakKeyDictionary()
+	_instances = weakref.WeakKeyDictionary()
 	title = ""
 	helpId = "NVDASettings"
 	shouldSuspendConfigProfileTriggers = True
@@ -102,25 +106,39 @@ def __new__(cls, *args, **kwargs):
 				"Creating new settings dialog (multiInstanceAllowed:{}). "
 				"State of _instances {!r}".format(multiInstanceAllowed, instancesState)
 			)
-		if state is cls._DIALOG_CREATED_STATE and not multiInstanceAllowed:
+		if state is cls.DialogState.CREATED and not multiInstanceAllowed:
 			raise SettingsDialog.MultiInstanceError("Only one instance of SettingsDialog can exist at a time")
-		if state is cls._DIALOG_DESTROYED_STATE and not multiInstanceAllowed:
+		if state is cls.DialogState.DESTROYED and not multiInstanceAllowed:
 			# the dialog has been destroyed by wx, but the instance is still available. This indicates there is something
 			# keeping it alive.
 			log.error("Opening new settings dialog while instance still exists: {!r}".format(firstMatchingInstance))
 		obj = super(SettingsDialog, cls).__new__(cls, *args, **kwargs)
-		SettingsDialog._instances[obj] = cls._DIALOG_CREATED_STATE
+		SettingsDialog._instances[obj] = cls.DialogState.CREATED
 		return obj
 
 	def _setInstanceDestroyedState(self):
-		if log.isEnabledFor(log.DEBUG):
-			instancesState = dict(SettingsDialog._instances)
-			log.debug(
-				"Setting state to destroyed for instance: {!r}\n"
-				"Current _instances {!r}".format(self, instancesState)
-			)
-		if self in SettingsDialog._instances:
-			SettingsDialog._instances[self] = self._DIALOG_DESTROYED_STATE
+		# prevent race condition with object deletion
+		# prevent deletion of the object while we work on it.
+		nonWeak: typing.Dict[SettingsDialog, SettingsDialog.DialogState] = dict(SettingsDialog._instances)
+
+		if (
+			self in SettingsDialog._instances
+			# Because destroy handlers are use evt.skip, _setInstanceDestroyedState may be called many times
+			# prevent noisy logging.
+			and self.DialogState.DESTROYED != SettingsDialog._instances[self]
+		):
+			if log.isEnabledFor(log.DEBUG):
+				instanceStatesGen = (
+					f"{instance.title} - {state.name}"
+					for instance, state in nonWeak.items()
+				)
+				instancesList = list(instanceStatesGen)
+				log.debug(
+					f"Setting state to destroyed for instance: {self.title} - {self.__class__.__qualname__} - {self}\n"
+					f"Current _instances {instancesList}"
+				)
+			SettingsDialog._instances[self] = self.DialogState.DESTROYED
+
 
 	def __init__(
 			self, parent,