Fix QErrorMessage test when using native dialogs

When the test is showing the error message over and over, it's not
waiting for the native dialog to actually become visible, and as
a result, hiding it has no effect and won't result in a call
to processResponse, where we got rid of the native dialog.

To fix this we explicitly release the native dialog when
encountering this corner case.

Add logic to QErrorMessage to test both native and non
native dialogs.

Pick-to: 6.5
Change-Id: I19ac3f463997aed1e66f646fdfcbb4d2459116d1
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>

2 files changed, 23 insertions, 0 deletions

diff --git a/tests/auto/widgets/dialogs/qerrormessage/CMakeLists.txt b/tests/auto/widgets/dialogs/qerrormessage/CMakeLists.txt
index ba4ea75b79..1cb63beea9 100644
--- a/tests/auto/widgets/dialogs/qerrormessage/CMakeLists.txt
+++ b/tests/auto/widgets/dialogs/qerrormessage/CMakeLists.txt
@@ -12,6 +12,7 @@ qt_internal_add_test(tst_qerrormessage
         tst_qerrormessage.cpp
     LIBRARIES
         Qt::Gui
+        Qt::GuiPrivate
         Qt::Widgets
 )
 
diff --git a/tests/auto/widgets/dialogs/qerrormessage/tst_qerrormessage.cpp b/tests/auto/widgets/dialogs/qerrormessage/tst_qerrormessage.cpp
index 97dad396e5..5cae8263dc 100644
--- a/tests/auto/widgets/dialogs/qerrormessage/tst_qerrormessage.cpp
+++ b/tests/auto/widgets/dialogs/qerrormessage/tst_qerrormessage.cpp
@@ -5,16 +5,38 @@
 #include <QDebug>
 #include <QCheckBox>
 
+#include <qpa/qplatformtheme.h>
+#include <private/qguiapplication_p.h>
+
 class tst_QErrorMessage : public QObject
 {
     Q_OBJECT
 
 private slots:
+    void initTestCase_data();
+    void init();
+
     void dontShowAgain();
     void dontShowCategoryAgain();
 
 };
 
+void tst_QErrorMessage::initTestCase_data()
+{
+    QTest::addColumn<bool>("useNativeDialog");
+    QTest::newRow("widget") << false;
+    if (const QPlatformTheme *theme = QGuiApplicationPrivate::platformTheme()) {
+        if (theme->usePlatformNativeDialog(QPlatformTheme::MessageDialog))
+            QTest::newRow("native") << true;
+    }
+}
+
+void tst_QErrorMessage::init()
+{
+    QFETCH_GLOBAL(bool, useNativeDialog);
+    qApp->setAttribute(Qt::AA_DontUseNativeDialogs, !useNativeDialog);
+}
+
 void tst_QErrorMessage::dontShowAgain()
 {
     QString plainString = QLatin1String("foo");