/****************************************************************************

**

** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).

** All rights reserved.

** Contact: Nokia Corporation (qt-info@nokia.com)

**

** This file is part of the test suite of the Qt Toolkit.

**

** $QT_BEGIN_LICENSE:LGPL$

** No Commercial Usage

** This file contains pre-release code and may not be distributed.

** You may use this file in accordance with the terms and conditions

** contained in the Technology Preview License Agreement accompanying

** this package.

**

** GNU Lesser General Public License Usage

** Alternatively, this file may be used under the terms of the GNU Lesser

** General Public License version 2.1 as published by the Free Software

** Foundation and appearing in the file LICENSE.LGPL included in the

** packaging of this file.  Please review the following information to

** ensure the GNU Lesser General Public License version 2.1 requirements

** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.

**

** In addition, as a special exception, Nokia gives you certain additional

** rights.  These rights are described in the Nokia Qt LGPL Exception

** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.

**

** If you have questions regarding the use of this file, please contact

** Nokia at qt-info@nokia.com.

**

**

**

**

**

**

**

**

** $QT_END_LICENSE$

**

****************************************************************************/

#include <QtTest/QtTest>

#include <qcoreapplication.h>

#include <qobject.h>

//TESTED_CLASS=

//TESTED_FILES=corelib/kernel/qobject.h corelib/kernel/qobject.cpp

class tst_QObjectPerformance : public QObject

{

    Q_OBJECT

public:

private slots:

    void emitToManyReceivers();

};

class SimpleSenderObject : public QObject

{

    Q_OBJECT

signals:

    void signal();

public:

    void emitSignal()

    {

        emit signal();

    }

};

class SimpleReceiverObject : public QObject

{

    Q_OBJECT

public slots:

    void slot()

    {

    }

};

void tst_QObjectPerformance::emitToManyReceivers()

{

    // ensure that emission times remain mostly linear as the number of receivers increase

    SimpleSenderObject sender;

    int elapsed = 0;

    const int increase = 3000;

    const int base = 5000;

    for (int i = 0; i < 4; ++i) {

        const int size = base + i * increase;

        const double increaseRatio = double(size) / (double)(size - increase);

        QList<SimpleReceiverObject *> receivers;

        for (int k = 0; k < size; ++k) {

            SimpleReceiverObject *receiver = new SimpleReceiverObject;

            QObject::connect(&sender, SIGNAL(signal()), receiver, SLOT(slot()));

            receivers.append(receiver);

        }

        QTime timer;

        timer.start();

        sender.emitSignal();

        int e = timer.elapsed();

        if (elapsed > 1) {

            qDebug() << size << "receivers, elapsed time" << e << "compared to previous time" << elapsed;

            QVERIFY(double(e) / double(elapsed) <= increaseRatio * 2.0);

        } else {

            qDebug() << size << "receivers, elapsed time" << e << "cannot be compared to previous, unmeasurable time";

        }

        elapsed = e;

        qDeleteAll(receivers);

        receivers.clear();

    }

}

QTEST_MAIN(tst_QObjectPerformance)

#include "tst_qobjectperformance.moc"