qtestsupport_core.cpp

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// Copyright (C) 2022 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
#include "qtestsupport_core.h"
 
#include <thread>
 
using namespace std::chrono_literals;
 
QT_BEGIN_NAMESPACE
 
void QTest::qSleep(int ms)
{
    QTest::qSleep(std::chrono::milliseconds{ms});
}
 
void QTest::qSleep(std::chrono::milliseconds msecs)
{
    Q_ASSERT(msecs > 0ms);
    std::this_thread::sleep_for(msecs);
}
 
Q_CORE_EXPORT void QTest::qWait(int msecs)
{
    qWait(std::chrono::milliseconds{msecs});
}
 
Q_CORE_EXPORT void QTest::qWait(std::chrono::milliseconds msecs)
{
    // Ideally this method would be implemented in terms of qWaitFor(), with a
    // predicate that always returns false, but qWaitFor() uses the 1-arg overload
    // of processEvents(), which doesn't handle events posted in this round of event
    // processing, which, together with the 10ms qSleep() after every processEvents(),
    // lead to a 10x slow-down in some webengine tests.
 
    Q_ASSERT(QCoreApplication::instance());
 
    using namespace std::chrono;
 
    QDeadlineTimer deadline(msecs, Qt::PreciseTimer);
 
    do {
        QCoreApplication::processEvents(QEventLoop::AllEvents, deadline);
        QCoreApplication::sendPostedEvents(nullptr, QEvent::DeferredDelete);
 
        // If dealine is Forever, processEvents() has already looped forever
        if (deadline.isForever())
            break;
 
        msecs = ceil<milliseconds>(deadline.remainingTimeAsDuration());
        if (msecs == 0ms)
            break;
 
        QTest::qSleep(std::min(10ms, msecs));
    } while (!deadline.hasExpired());
}
 
QT_END_NAMESPACE