4 files changed, 37 insertions, 1 deletions
diff --git a/src/widgets/kernel/qwidget_qpa.cpp b/src/widgets/kernel/qwidget_qpa.cpp
index ae8a0b25b9..18045e3b09 100644
--- a/src/widgets/kernel/qwidget_qpa.cpp
+++ b/src/widgets/kernel/qwidget_qpa.cpp
@@ -506,9 +506,9 @@ void QWidgetPrivate::show_sys()
 
     QWindow *window = q->windowHandle();
 
+    q->setAttribute(Qt::WA_Mapped);
     if (q->testAttribute(Qt::WA_DontShowOnScreen)) {
         invalidateBuffer(q->rect());
-        q->setAttribute(Qt::WA_Mapped);
         if (q->isWindow() && q->windowModality() != Qt::NonModal && window) {
             // add our window to the modal window list
             QGuiApplicationPrivate::showModalWindow(window);
diff --git a/src/widgets/kernel/qwidgetwindow.cpp b/src/widgets/kernel/qwidgetwindow.cpp
index e977ab3d6f..22e15e23fe 100644
--- a/src/widgets/kernel/qwidgetwindow.cpp
+++ b/src/widgets/kernel/qwidgetwindow.cpp
@@ -713,6 +713,10 @@ void QWidgetWindow::handleWindowStateChangedEvent(QWindowStateChangeEvent *event
         break;
     }
 
+    // Note that widgetState == m_widget->data->window_state when triggered by QWidget::setWindowState().
+    if (!(widgetState & Qt::WindowMinimized))
+        m_widget->setAttribute(Qt::WA_Mapped);
+
     // Sent event if the state changed (that is, it is not triggered by
     // QWidget::setWindowState(), which also sends an event to the widget).
     if (widgetState != int(m_widget->data->window_state)) {
diff --git a/tests/auto/widgets/kernel/qwidget/tst_qwidget.cpp b/tests/auto/widgets/kernel/qwidget/tst_qwidget.cpp
index 03d6c1cdbd..7bb5fd4614 100644
--- a/tests/auto/widgets/kernel/qwidget/tst_qwidget.cpp
+++ b/tests/auto/widgets/kernel/qwidget/tst_qwidget.cpp
@@ -7192,6 +7192,10 @@ void tst_QWidget::hideOpaqueChildWhileHidden()
 #if !defined(Q_OS_WINCE)
 void tst_QWidget::updateWhileMinimized()
 {
+#ifdef Q_OS_UNIX
+    if (qgetenv("XDG_CURRENT_DESKTOP").contains("Unity"))
+        QSKIP("This test fails on Unity."); // Minimized windows are not unmapped for some reason.
+#endif // Q_OS_UNIX
     UpdateWidget widget;
    // Filter out activation change and focus events to avoid update() calls in QWidget.
     widget.updateOnActivationChangeAndFocusIn = false;
diff --git a/tests/auto/widgets/kernel/qwidget_window/tst_qwidget_window.cpp b/tests/auto/widgets/kernel/qwidget_window/tst_qwidget_window.cpp
index 1bbbfd610e..f5585c583a 100644
--- a/tests/auto/widgets/kernel/qwidget_window/tst_qwidget_window.cpp
+++ b/tests/auto/widgets/kernel/qwidget_window/tst_qwidget_window.cpp
@@ -91,6 +91,8 @@ private slots:
     void tst_showWithoutActivating();
     void tst_paintEventOnSecondShow();
 
+    void obscuredNativeMapped();
+
 #ifndef QT_NO_DRAGANDDROP
     void tst_dnd();
 #endif
@@ -368,6 +370,32 @@ void tst_QWidget_window::tst_paintEventOnSecondShow()
     QTRY_VERIFY(w.paintEventReceived);
 }
 
+// QTBUG-33520, a toplevel fully obscured by native children should still receive Qt::WA_Mapped
+void tst_QWidget_window::obscuredNativeMapped()
+{
+    enum { size = 200 };
+
+    QWidget topLevel;
+    topLevel.setWindowFlags(Qt::FramelessWindowHint);
+    QWidget *child = new QWidget(&topLevel);
+    child->resize(size, size);
+    topLevel.resize(size, size);
+    topLevel.move(QGuiApplication::primaryScreen()->availableGeometry().center() - QPoint(size /2 , size / 2));
+    child->winId();
+    topLevel.show();
+    QTRY_VERIFY(topLevel.testAttribute(Qt::WA_Mapped));
+#if defined(Q_OS_MAC)
+    QSKIP("This test fails on Mac."); // Minimized windows are not unmapped for some reason.
+#elif defined(Q_OS_UNIX)
+    if (qgetenv("XDG_CURRENT_DESKTOP").contains("Unity"))
+        QSKIP("This test fails on Unity."); // Minimized windows are not unmapped for some reason.
+#endif // Q_OS_UNIX
+    topLevel.setWindowState(Qt::WindowMinimized);
+    QTRY_VERIFY(!topLevel.testAttribute(Qt::WA_Mapped));
+    topLevel.setWindowState(Qt::WindowNoState);
+    QTRY_VERIFY(topLevel.testAttribute(Qt::WA_Mapped));
+}
+
 #ifndef QT_NO_DRAGANDDROP
 
 /* DnD test for QWidgetWindow (handleDrag*Event() functions).