Make sure posted events are always sent when calling processEvents() on Win32

After 31f1ff910, posted events could be delayed by a previous call to
processEvents(). This causes some tests to randomly fail, so bring back
the invariant that processEvents() will always call sendPostedEvents() when
called "manually" (i.e. not from exec()).

Reviewed-by: Prasanth Ullattil

2 files changed, 41 insertions, 0 deletions

diff --git a/src/corelib/kernel/qeventdispatcher_win.cpp b/src/corelib/kernel/qeventdispatcher_win.cpp
index 3050b82..0518e24 100644
--- a/src/corelib/kernel/qeventdispatcher_win.cpp
+++ b/src/corelib/kernel/qeventdispatcher_win.cpp
@@ -675,6 +675,11 @@ bool QEventDispatcherWin32::processEvents(QEventLoop::ProcessEventsFlags flags)
     bool seenWM_QT_SENDPOSTEDEVENTS = false;
     bool needWM_QT_SENDPOSTEDEVENTS = false;
     do {
+        if (! (flags & QEventLoop::EventLoopExec)) {
+            // when called "manually", always send posted events
+            QCoreApplicationPrivate::sendPostedEvents(0, 0, d->threadData);
+        }
+
         DWORD waitRet = 0;
         HANDLE pHandles[MAXIMUM_WAIT_OBJECTS - 1];
         QVarLengthArray<MSG> processedTimers;
diff --git a/tests/auto/qcoreapplication/tst_qcoreapplication.cpp b/tests/auto/qcoreapplication/tst_qcoreapplication.cpp
index c5f06e2..3c61f81 100644
--- a/tests/auto/qcoreapplication/tst_qcoreapplication.cpp
+++ b/tests/auto/qcoreapplication/tst_qcoreapplication.cpp
@@ -58,6 +58,7 @@ private slots:
 #endif
     void applicationPid();
     void globalPostedEventsCount();
+    void processEventsAlwaysSendsPostedEvents();
 };
 
 class EventSpy : public QObject
@@ -488,5 +489,40 @@ void tst_QCoreApplication::globalPostedEventsCount()
     QCOMPARE(x.globalPostedEventsCount, expected);
 }
 
+class ProcessEventsAlwaysSendsPostedEventsObject : public QObject
+{
+public:
+    int counter;
+
+    inline ProcessEventsAlwaysSendsPostedEventsObject()
+        : counter(0)
+    { }
+
+    bool event(QEvent *event)
+    {
+        if (event->type() == QEvent::User)
+            ++counter;
+        return QObject::event(event);
+    }
+};
+
+void tst_QCoreApplication::processEventsAlwaysSendsPostedEvents()
+{
+    int argc = 1;
+    char *argv[] = { "tst_qcoreapplication" };
+    QCoreApplication app(argc, argv);
+
+    ProcessEventsAlwaysSendsPostedEventsObject object;
+    QTime t;
+    t.start();
+    int i = 1;
+    do {
+        QCoreApplication::postEvent(&object, new QEvent(QEvent::User));
+        QCoreApplication::processEvents();
+        QCOMPARE(object.counter, i);
+        ++i;
+    } while (t.elapsed() < 3000);
+}
+
 QTEST_APPLESS_MAIN(tst_QCoreApplication)
 #include "tst_qcoreapplication.moc"