Accessibility: Fix crash when updating in dtor

This happens for example when running several tests.
Widgets in destructor should be treated as invalid
since their window pointer and other properties are
no longer valid.

When deleting a window containing only a table view
there would be a table model reset update comming from
the window being destroyed.

Change-Id: Ia387c814333ce373fe132b189fc180787e36cdd5
Reviewed-by: Jan Arve Sæther <jan-arve.saether@digia.com>

2 files changed, 10 insertions, 0 deletions

diff --git a/src/widgets/accessible/qaccessiblewidget.cpp b/src/widgets/accessible/qaccessiblewidget.cpp
index 2b8e1a7036..dcbf276356 100644
--- a/src/widgets/accessible/qaccessiblewidget.cpp
+++ b/src/widgets/accessible/qaccessiblewidget.cpp
@@ -55,6 +55,7 @@
 #include <QRubberBand>
 #include <QFocusFrame>
 #include <QMenu>
+#include <QtWidgets/private/qwidget_p.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -152,6 +153,7 @@ QString Q_WIDGETS_EXPORT qt_accHotKey(const QString &text)
     return QString();
 }
 
+// ### inherit QAccessibleObjectPrivate
 class QAccessibleWidgetPrivate
 {
 public:
@@ -202,6 +204,13 @@ QAccessibleWidget::QAccessibleWidget(QWidget *w, QAccessible::Role role, const Q
     d->name = name;
 }
 
+bool QAccessibleWidget::isValid() const
+{
+    if (!object() || static_cast<QWidget *>(object())->d_func()->data.in_destructor)
+        return false;
+    return QAccessibleObject::isValid();
+}
+
 /*! \reimp */
 QWindow *QAccessibleWidget::window() const
 {
diff --git a/src/widgets/accessible/qaccessiblewidget_p.h b/src/widgets/accessible/qaccessiblewidget_p.h
index 803dc71409..cb1ce37734 100644
--- a/src/widgets/accessible/qaccessiblewidget_p.h
+++ b/src/widgets/accessible/qaccessiblewidget_p.h
@@ -56,6 +56,7 @@ class Q_WIDGETS_EXPORT QAccessibleWidget : public QAccessibleObject, public QAcc
 {
 public:
     explicit QAccessibleWidget(QWidget *o, QAccessible::Role r = QAccessible::Client, const QString& name = QString());
+    bool isValid() const;
 
     QWindow *window() const;
     int childCount() const;