tst_qquickapplication: change test case 'state' to be more stable

Qt-5.4 integration can sometimes fail on this test. We have not
succeeded reproducing it, but from reading the test code, it seems
likely that the problem might come from already pending state
events queued before the test starts. Since the test cannot know if
the platform will queue state events while spinning the event loop
(waitForEvents), this patch will instead only flush already queued
events, which should be less prone to side effects.

Change-Id: I134f98ba35faa4d9213ee658ebcbe76b390b5516
Reviewed-by: Yoann Lopes <yoann.lopes@theqtcompany.com>
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@theqtcompany.com>

1 files changed, 7 insertions, 8 deletions

diff --git a/tests/auto/quick/qquickapplication/tst_qquickapplication.cpp b/tests/auto/quick/qquickapplication/tst_qquickapplication.cpp
index f803a63fd7..cc6fac5b39 100644
--- a/tests/auto/quick/qquickapplication/tst_qquickapplication.cpp
+++ b/tests/auto/quick/qquickapplication/tst_qquickapplication.cpp
@@ -132,31 +132,30 @@ void tst_qquickapplication::state()
     QQuickWindow window;
     item->setParentItem(window.contentItem());
 
-    // initial state should be ApplicationInactive
-    QCOMPARE(Qt::ApplicationState(item->property("state").toInt()), Qt::ApplicationInactive);
-    QCOMPARE(Qt::ApplicationState(item->property("state2").toInt()), Qt::ApplicationInactive);
-
     // If the platform plugin has the ApplicationState capability, state changes originate from it
     // as a result of a system event. We therefore have to simulate these events here.
     if (QGuiApplicationPrivate::platformIntegration()->hasCapability(QPlatformIntegration::ApplicationState)) {
 
+        // Flush pending events, in case the platform have already queued real application state events
+        QWindowSystemInterface::flushWindowSystemEvents();
+
         QWindowSystemInterface::handleApplicationStateChanged(Qt::ApplicationActive);
-        QTest::waitForEvents();
+        QWindowSystemInterface::flushWindowSystemEvents();
         QCOMPARE(Qt::ApplicationState(item->property("state").toInt()), Qt::ApplicationActive);
         QCOMPARE(Qt::ApplicationState(item->property("state2").toInt()), Qt::ApplicationActive);
 
         QWindowSystemInterface::handleApplicationStateChanged(Qt::ApplicationInactive);
-        QTest::waitForEvents();
+        QWindowSystemInterface::flushWindowSystemEvents();
         QCOMPARE(Qt::ApplicationState(item->property("state").toInt()), Qt::ApplicationInactive);
         QCOMPARE(Qt::ApplicationState(item->property("state2").toInt()), Qt::ApplicationInactive);
 
         QWindowSystemInterface::handleApplicationStateChanged(Qt::ApplicationSuspended);
-        QTest::waitForEvents();
+        QWindowSystemInterface::flushWindowSystemEvents();
         QCOMPARE(Qt::ApplicationState(item->property("state").toInt()), Qt::ApplicationSuspended);
         QCOMPARE(Qt::ApplicationState(item->property("state2").toInt()), Qt::ApplicationSuspended);
 
         QWindowSystemInterface::handleApplicationStateChanged(Qt::ApplicationHidden);
-        QTest::waitForEvents();
+        QWindowSystemInterface::flushWindowSystemEvents();
         QCOMPARE(Qt::ApplicationState(item->property("state").toInt()), Qt::ApplicationHidden);
         QCOMPARE(Qt::ApplicationState(item->property("state2").toInt()), Qt::ApplicationHidden);