kwin/src/wayland/autotests/client/test_wayland_surface.cpp

/********************************************************************
Copyright 2014  Martin Gräßlin <mgraesslin@kde.org>

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) version 3, or any
later version accepted by the membership of KDE e.V. (or its
successor approved by the membership of KDE e.V.), which shall
act as a proxy defined in Section 6 of version 3 of the license.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library.  If not, see <http://www.gnu.org/licenses/>.
*********************************************************************/
// Qt
#include <QtTest/QtTest>
#include <QImage>
#include <QPainter>
// KWin
#include "../../src/client/compositor.h"
#include "../../src/client/connection_thread.h"
#include "../../src/client/event_queue.h"
#include "../../src/client/output.h"
#include "../../src/client/surface.h"
#include "../../src/client/region.h"
#include "../../src/client/registry.h"
#include "../../src/client/shm_pool.h"
#include "../../src/server/buffer_interface.h"
#include "../../src/server/compositor_interface.h"
#include "../../src/server/display.h"
#include "../../src/server/surface_interface.h"
// Wayland
#include <wayland-client-protocol.h>

class TestWaylandSurface : public QObject
{
    Q_OBJECT
public:
    explicit TestWaylandSurface(QObject *parent = nullptr);
private Q_SLOTS:
    void init();
    void cleanup();

    void testStaticAccessor();
    void testDamage();
    void testFrameCallback();
    void testAttachBuffer();
    void testMultipleSurfaces();
    void testOpaque();
    void testInput();
    void testScale();
    void testDestroy();
    void testUnmapOfNotMappedSurface();
    void testDamageTracking();
    void testSurfaceAt();
    void testDestroyAttachedBuffer();
    void testDestroyWithPendingCallback();
    void testOutput();
    void testDisconnect();

private:
    KWayland::Server::Display *m_display;
    KWayland::Server::CompositorInterface *m_compositorInterface;
    KWayland::Client::ConnectionThread *m_connection;
    KWayland::Client::Compositor *m_compositor;
    KWayland::Client::ShmPool *m_shm;
    KWayland::Client::EventQueue *m_queue;
    QThread *m_thread;
};

static const QString s_socketName = QStringLiteral("kwin-test-wayland-surface-0");

TestWaylandSurface::TestWaylandSurface(QObject *parent)
    : QObject(parent)
    , m_display(nullptr)
    , m_compositorInterface(nullptr)
    , m_connection(nullptr)
    , m_compositor(nullptr)
    , m_thread(nullptr)
{
}

void TestWaylandSurface::init()
{
    using namespace KWayland::Server;
    delete m_display;
    m_display = new Display(this);
    m_display->setSocketName(s_socketName);
    m_display->start();
    QVERIFY(m_display->isRunning());
    m_display->createShm();

    m_compositorInterface = m_display->createCompositor(m_display);
    QVERIFY(m_compositorInterface);
    m_compositorInterface->create();
    QVERIFY(m_compositorInterface->isValid());

    // setup connection
    m_connection = new KWayland::Client::ConnectionThread;
    QSignalSpy connectedSpy(m_connection, SIGNAL(connected()));
    m_connection->setSocketName(s_socketName);

    m_thread = new QThread(this);
    m_connection->moveToThread(m_thread);
    m_thread->start();

    /*connect(QCoreApplication::eventDispatcher(), &QAbstractEventDispatcher::aboutToBlock, m_connection,
        [this]() {
            if (m_connection->display()) {
                wl_display_flush(m_connection->display());
            }
        }
    );*/

    m_connection->initConnection();
    QVERIFY(connectedSpy.wait());

    m_queue = new KWayland::Client::EventQueue(this);
    QVERIFY(!m_queue->isValid());
    m_queue->setup(m_connection);
    QVERIFY(m_queue->isValid());

    KWayland::Client::Registry registry;
    registry.setEventQueue(m_queue);
    QSignalSpy compositorSpy(&registry, SIGNAL(compositorAnnounced(quint32,quint32)));
    QSignalSpy shmSpy(&registry, SIGNAL(shmAnnounced(quint32,quint32)));
    QSignalSpy allAnnounced(&registry, SIGNAL(interfacesAnnounced()));
    QVERIFY(allAnnounced.isValid());
    QVERIFY(shmSpy.isValid());
    registry.create(m_connection->display());
    QVERIFY(registry.isValid());
    registry.setup();
    QVERIFY(allAnnounced.wait());
    QVERIFY(!compositorSpy.isEmpty());
    QVERIFY(!shmSpy.isEmpty());

    m_compositor = registry.createCompositor(compositorSpy.first().first().value<quint32>(), compositorSpy.first().last().value<quint32>(), this);
    QVERIFY(m_compositor->isValid());
    m_shm = registry.createShmPool(shmSpy.first().first().value<quint32>(), shmSpy.first().last().value<quint32>(), this);
    QVERIFY(m_shm->isValid());
}

void TestWaylandSurface::cleanup()
{
    if (m_compositor) {
        delete m_compositor;
        m_compositor = nullptr;
    }
    if (m_shm) {
        delete m_shm;
        m_shm = nullptr;
    }
    if (m_queue) {
        delete m_queue;
        m_queue = nullptr;
    }
    if (m_thread) {
        m_thread->quit();
        m_thread->wait();
        delete m_thread;
        m_thread = nullptr;
    }
    delete m_connection;
    m_connection = nullptr;

    delete m_compositorInterface;
    m_compositorInterface = nullptr;

    delete m_display;
    m_display = nullptr;
}

void TestWaylandSurface::testStaticAccessor()
{
    QSignalSpy serverSurfaceCreated(m_compositorInterface, SIGNAL(surfaceCreated(KWayland::Server::SurfaceInterface*)));
    QVERIFY(serverSurfaceCreated.isValid());

    QVERIFY(!KWayland::Server::SurfaceInterface::get(nullptr));
    QVERIFY(!KWayland::Server::SurfaceInterface::get(1, nullptr));
    QVERIFY(KWayland::Client::Surface::all().isEmpty());
    KWayland::Client::Surface *s1 = m_compositor->createSurface();
    QVERIFY(s1->isValid());
    QCOMPARE(KWayland::Client::Surface::all().count(), 1);
    QCOMPARE(KWayland::Client::Surface::all().first(), s1);
    QCOMPARE(KWayland::Client::Surface::get(*s1), s1);
    QVERIFY(serverSurfaceCreated.wait());
    auto serverSurface1 = serverSurfaceCreated.first().first().value<KWayland::Server::SurfaceInterface*>();
    QVERIFY(serverSurface1);
    QCOMPARE(KWayland::Server::SurfaceInterface::get(serverSurface1->resource()), serverSurface1);
    QCOMPARE(KWayland::Server::SurfaceInterface::get(serverSurface1->id(), serverSurface1->client()), serverSurface1);

    QVERIFY(!s1->size().isValid());
    QSignalSpy sizeChangedSpy(s1, SIGNAL(sizeChanged(QSize)));
    QVERIFY(sizeChangedSpy.isValid());
    const QSize testSize(200, 300);
    s1->setSize(testSize);
    QCOMPARE(s1->size(), testSize);
    QCOMPARE(sizeChangedSpy.count(), 1);
    QCOMPARE(sizeChangedSpy.first().first().toSize(), testSize);

    // add another surface
    KWayland::Client::Surface *s2 = m_compositor->createSurface();
    QVERIFY(s2->isValid());
    QCOMPARE(KWayland::Client::Surface::all().count(), 2);
    QCOMPARE(KWayland::Client::Surface::all().first(), s1);
    QCOMPARE(KWayland::Client::Surface::all().last(), s2);
    QCOMPARE(KWayland::Client::Surface::get(*s1), s1);
    QCOMPARE(KWayland::Client::Surface::get(*s2), s2);
    serverSurfaceCreated.clear();
    QVERIFY(serverSurfaceCreated.wait());
    auto serverSurface2 = serverSurfaceCreated.first().first().value<KWayland::Server::SurfaceInterface*>();
    QVERIFY(serverSurface2);
    QCOMPARE(KWayland::Server::SurfaceInterface::get(serverSurface1->resource()), serverSurface1);
    QCOMPARE(KWayland::Server::SurfaceInterface::get(serverSurface1->id(), serverSurface1->client()), serverSurface1);
    QCOMPARE(KWayland::Server::SurfaceInterface::get(serverSurface2->resource()), serverSurface2);
    QCOMPARE(KWayland::Server::SurfaceInterface::get(serverSurface2->id(), serverSurface2->client()), serverSurface2);

    // delete s2 again
    delete s2;
    QCOMPARE(KWayland::Client::Surface::all().count(), 1);
    QCOMPARE(KWayland::Client::Surface::all().first(), s1);
    QCOMPARE(KWayland::Client::Surface::get(*s1), s1);

    // and finally delete the last one
    delete s1;
    QVERIFY(KWayland::Client::Surface::all().isEmpty());
    QVERIFY(!KWayland::Client::Surface::get(nullptr));
    QSignalSpy unboundSpy(serverSurface1, &KWayland::Server::Resource::unbound);
    QVERIFY(unboundSpy.isValid());
    QVERIFY(unboundSpy.wait());
    QVERIFY(!KWayland::Server::SurfaceInterface::get(nullptr));
    QVERIFY(!KWayland::Server::SurfaceInterface::get(1, nullptr));
}

void TestWaylandSurface::testDamage()
{
    QSignalSpy serverSurfaceCreated(m_compositorInterface, SIGNAL(surfaceCreated(KWayland::Server::SurfaceInterface*)));
    QVERIFY(serverSurfaceCreated.isValid());
    KWayland::Client::Surface *s = m_compositor->createSurface();
    QVERIFY(serverSurfaceCreated.wait());
    KWayland::Server::SurfaceInterface *serverSurface = serverSurfaceCreated.first().first().value<KWayland::Server::SurfaceInterface*>();
    QVERIFY(serverSurface);
    QCOMPARE(serverSurface->damage(), QRegion());
    QVERIFY(serverSurface->parentResource());
    QVERIFY(!serverSurface->isMapped());

    QSignalSpy damageSpy(serverSurface, SIGNAL(damaged(QRegion)));
    QVERIFY(damageSpy.isValid());

    // send damage without a buffer
    s->damage(QRect(0, 0, 100, 100));
    s->commit(KWayland::Client::Surface::CommitFlag::None);
    wl_display_flush(m_connection->display());
    QCoreApplication::processEvents();
    QCoreApplication::processEvents();
    QVERIFY(damageSpy.isEmpty());
    QVERIFY(!serverSurface->isMapped());

    QImage img(QSize(10, 10), QImage::Format_ARGB32_Premultiplied);
    img.fill(Qt::black);
    auto b = m_shm->createBuffer(img);
    s->attachBuffer(b);
    s->damage(QRect(0, 0, 10, 10));
    s->commit(KWayland::Client::Surface::CommitFlag::None);
    QVERIFY(damageSpy.wait());
    QCOMPARE(serverSurface->damage(), QRegion(0, 0, 10, 10));
    QCOMPARE(damageSpy.first().first().value<QRegion>(), QRegion(0, 0, 10, 10));
    QVERIFY(serverSurface->isMapped());

    // damage multiple times
    QRegion testRegion(5, 8, 3, 6);
    testRegion = testRegion.united(QRect(10, 20, 30, 15));
    img = QImage(QSize(40, 35), QImage::Format_ARGB32_Premultiplied);
    img.fill(Qt::black);
    b = m_shm->createBuffer(img);
    s->attachBuffer(b);
    s->damage(testRegion);
    damageSpy.clear();
    s->commit(KWayland::Client::Surface::CommitFlag::None);
    QVERIFY(damageSpy.wait());
    QCOMPARE(serverSurface->damage(), testRegion);
    QCOMPARE(damageSpy.first().first().value<QRegion>(), testRegion);
    QVERIFY(serverSurface->isMapped());
}

void TestWaylandSurface::testFrameCallback()
{
    QSignalSpy serverSurfaceCreated(m_compositorInterface, SIGNAL(surfaceCreated(KWayland::Server::SurfaceInterface*)));
    QVERIFY(serverSurfaceCreated.isValid());
    KWayland::Client::Surface *s = m_compositor->createSurface();
    QVERIFY(serverSurfaceCreated.wait());
    KWayland::Server::SurfaceInterface *serverSurface = serverSurfaceCreated.first().first().value<KWayland::Server::SurfaceInterface*>();
    QVERIFY(serverSurface);

    QSignalSpy damageSpy(serverSurface, SIGNAL(damaged(QRegion)));
    QVERIFY(damageSpy.isValid());

    QSignalSpy frameRenderedSpy(s, SIGNAL(frameRendered()));
    QVERIFY(frameRenderedSpy.isValid());
    QImage img(QSize(10, 10), QImage::Format_ARGB32_Premultiplied);
    img.fill(Qt::black);
    auto b = m_shm->createBuffer(img);
    s->attachBuffer(b);
    s->damage(QRect(0, 0, 10, 10));
    s->commit();
    QVERIFY(damageSpy.wait());
    serverSurface->frameRendered(10);
    QVERIFY(frameRenderedSpy.isEmpty());
    QVERIFY(frameRenderedSpy.wait());
    QVERIFY(!frameRenderedSpy.isEmpty());
}

void TestWaylandSurface::testAttachBuffer()
{
    // create the surface
    QSignalSpy serverSurfaceCreated(m_compositorInterface, SIGNAL(surfaceCreated(KWayland::Server::SurfaceInterface*)));
    QVERIFY(serverSurfaceCreated.isValid());
    KWayland::Client::Surface *s = m_compositor->createSurface();
    QVERIFY(serverSurfaceCreated.wait());
    KWayland::Server::SurfaceInterface *serverSurface = serverSurfaceCreated.first().first().value<KWayland::Server::SurfaceInterface*>();
    QVERIFY(serverSurface);

    // create three images
    QImage black(24, 24, QImage::Format_RGB32);
    black.fill(Qt::black);
    QImage red(24, 24, QImage::Format_ARGB32); //Note - deliberately not premultiplied
    red.fill(QColor(255, 0, 0, 128));
    QImage blue(24, 24, QImage::Format_ARGB32_Premultiplied);
    blue.fill(QColor(0, 0, 255, 128));

    wl_buffer *blackBuffer = *(m_shm->createBuffer(black).data());
    auto redBuffer = m_shm->createBuffer(red);
    auto blueBuffer = m_shm->createBuffer(blue).toStrongRef();

    QCOMPARE(blueBuffer->format(), KWayland::Client::Buffer::Format::ARGB32);
    QCOMPARE(blueBuffer->size(), blue.size());
    QVERIFY(!blueBuffer->isReleased());
    QVERIFY(!blueBuffer->isUsed());
    QCOMPARE(blueBuffer->stride(), blue.bytesPerLine());

    s->attachBuffer(redBuffer.data());
    s->attachBuffer(blackBuffer);
    s->damage(QRect(0, 0, 24, 24));
    s->commit(KWayland::Client::Surface::CommitFlag::None);
    QSignalSpy damageSpy(serverSurface, SIGNAL(damaged(QRegion)));
    QVERIFY(damageSpy.isValid());
    QSignalSpy unmappedSpy(serverSurface, SIGNAL(unmapped()));
    QVERIFY(unmappedSpy.isValid());
    QVERIFY(damageSpy.wait());
    QVERIFY(unmappedSpy.isEmpty());

    // now the ServerSurface should have the black image attached as a buffer
    KWayland::Server::BufferInterface *buffer = serverSurface->buffer();
    buffer->ref();
    QVERIFY(buffer->shmBuffer());
    QCOMPARE(buffer->data(), black);
    QCOMPARE(buffer->data().format(), QImage::Format_RGB32);

    // render another frame
    s->attachBuffer(redBuffer);
    s->damage(QRect(0, 0, 24, 24));
    s->commit(KWayland::Client::Surface::CommitFlag::None);
    damageSpy.clear();
    QVERIFY(damageSpy.wait());
    QVERIFY(unmappedSpy.isEmpty());
    KWayland::Server::BufferInterface *buffer2 = serverSurface->buffer();
    buffer2->ref();
    QVERIFY(buffer2->shmBuffer());
    QCOMPARE(buffer2->data().format(), QImage::Format_ARGB32_Premultiplied);
    QCOMPARE(buffer2->data().width(), 24);
    QCOMPARE(buffer2->data().height(), 24);
    for (int i = 0; i < 24; ++i) {
        for (int j = 0; j < 24; ++j) {
            // it's premultiplied in the format
            QCOMPARE(buffer2->data().pixel(i, j), qRgba(128, 0, 0, 128));
        }
    }
    buffer2->unref();
    QVERIFY(buffer2->isReferenced());
    QVERIFY(!redBuffer.data()->isReleased());

    // render another frame
    blueBuffer->setUsed(true);
    QVERIFY(blueBuffer->isUsed());
    s->attachBuffer(blueBuffer.data());
    s->damage(QRect(0, 0, 24, 24));
    QSignalSpy frameRenderedSpy(s, SIGNAL(frameRendered()));
    QVERIFY(frameRenderedSpy.isValid());
    s->commit();
    damageSpy.clear();
    QVERIFY(damageSpy.wait());
    QVERIFY(unmappedSpy.isEmpty());
    QVERIFY(!buffer2->isReferenced());
    delete buffer2;
    // TODO: we should have a signal on when the Buffer gets released
    QCoreApplication::processEvents(QEventLoop::WaitForMoreEvents);
    if (!redBuffer.data()->isReleased()) {
        QCoreApplication::processEvents(QEventLoop::WaitForMoreEvents);
    }
    QVERIFY(redBuffer.data()->isReleased());

    KWayland::Server::BufferInterface *buffer3 = serverSurface->buffer();
    buffer3->ref();
    QVERIFY(buffer3->shmBuffer());
    QCOMPARE(buffer3->data().format(), QImage::Format_ARGB32_Premultiplied);
    QCOMPARE(buffer3->data().width(), 24);
    QCOMPARE(buffer3->data().height(), 24);
    for (int i = 0; i < 24; ++i) {
        for (int j = 0; j < 24; ++j) {
            // it's premultiplied in the format
            QCOMPARE(buffer3->data().pixel(i, j), qRgba(0, 0, 128, 128));
        }
    }
    buffer3->unref();
    QVERIFY(buffer3->isReferenced());

    serverSurface->frameRendered(1);
    QVERIFY(frameRenderedSpy.wait());

    // commit a different value shouldn't change our buffer
    QCOMPARE(serverSurface->buffer(), buffer3);
    QVERIFY(serverSurface->input().isNull());
    damageSpy.clear();
    s->setInputRegion(m_compositor->createRegion(QRegion(0, 0, 24, 24)).get());
    s->commit(KWayland::Client::Surface::CommitFlag::None);
    wl_display_flush(m_connection->display());
    QCoreApplication::processEvents();
    QCoreApplication::processEvents();
    QCOMPARE(serverSurface->input(), QRegion(0, 0, 24, 24));
    QCOMPARE(serverSurface->buffer(), buffer3);
    QVERIFY(damageSpy.isEmpty());
    QVERIFY(unmappedSpy.isEmpty());
    QVERIFY(serverSurface->isMapped());

    // clear the surface
    s->attachBuffer(blackBuffer);
    s->damage(QRect(0, 0, 1, 1));
    // TODO: better method
    s->attachBuffer((wl_buffer*)nullptr);
    s->damage(QRect(0, 0, 10, 10));
    s->commit(KWayland::Client::Surface::CommitFlag::None);
    QVERIFY(unmappedSpy.wait());
    QVERIFY(!unmappedSpy.isEmpty());
    QCOMPARE(unmappedSpy.count(), 1);
    QVERIFY(damageSpy.isEmpty());
    QVERIFY(!serverSurface->isMapped());

    // TODO: add signal test on release
    buffer->unref();
}

void TestWaylandSurface::testMultipleSurfaces()
{
    using namespace KWayland::Client;
    using namespace KWayland::Server;
    Registry registry;
    QSignalSpy shmSpy(&registry, SIGNAL(shmAnnounced(quint32,quint32)));
    registry.create(m_connection->display());
    QVERIFY(registry.isValid());
    registry.setup();
    QVERIFY(shmSpy.wait());

    ShmPool pool1;
    ShmPool pool2;
    pool1.setup(registry.bindShm(shmSpy.first().first().value<quint32>(), shmSpy.first().last().value<quint32>()));
    pool2.setup(registry.bindShm(shmSpy.first().first().value<quint32>(), shmSpy.first().last().value<quint32>()));
    QVERIFY(pool1.isValid());
    QVERIFY(pool2.isValid());

    // create the surfaces
    QSignalSpy serverSurfaceCreated(m_compositorInterface, SIGNAL(surfaceCreated(KWayland::Server::SurfaceInterface*)));
    QVERIFY(serverSurfaceCreated.isValid());
    QScopedPointer<Surface> s1(m_compositor->createSurface());
    QVERIFY(serverSurfaceCreated.wait());
    SurfaceInterface *serverSurface1 = serverSurfaceCreated.first().first().value<KWayland::Server::SurfaceInterface*>();
    QVERIFY(serverSurface1);
    //second surface
    QScopedPointer<Surface> s2(m_compositor->createSurface());
    QVERIFY(serverSurfaceCreated.wait());
    SurfaceInterface *serverSurface2 = serverSurfaceCreated.last().first().value<KWayland::Server::SurfaceInterface*>();
    QVERIFY(serverSurface2);
    QVERIFY(serverSurface1->resource() != serverSurface2->resource());

    // create two images
    QImage black(24, 24, QImage::Format_RGB32);
    black.fill(Qt::black);
    QImage red(24, 24, QImage::Format_ARGB32_Premultiplied);
    red.fill(QColor(255, 0, 0, 128));

    auto blackBuffer = pool1.createBuffer(black);
    auto redBuffer = pool2.createBuffer(red);

    s1->attachBuffer(blackBuffer);
    s1->damage(QRect(0, 0, 24, 24));
    s1->commit(Surface::CommitFlag::None);
    QSignalSpy damageSpy1(serverSurface1, SIGNAL(damaged(QRegion)));
    QVERIFY(damageSpy1.isValid());
    QVERIFY(damageSpy1.wait());

    // now the ServerSurface should have the black image attached as a buffer
    BufferInterface *buffer1 = serverSurface1->buffer();
    QVERIFY(buffer1);
    QImage buffer1Data = buffer1->data();
    QCOMPARE(buffer1Data, black);
    // accessing the same buffer is OK
    QImage buffer1Data2 = buffer1->data();
    QCOMPARE(buffer1Data2, buffer1Data);
    buffer1Data = QImage();
    QVERIFY(buffer1Data.isNull());
    buffer1Data2 = QImage();
    QVERIFY(buffer1Data2.isNull());

    // attach a buffer for the other surface
    s2->attachBuffer(redBuffer);
    s2->damage(QRect(0, 0, 24, 24));
    s2->commit(Surface::CommitFlag::None);
    QSignalSpy damageSpy2(serverSurface2, SIGNAL(damaged(QRegion)));
    QVERIFY(damageSpy2.isValid());
    QVERIFY(damageSpy2.wait());

    BufferInterface *buffer2 = serverSurface2->buffer();
    QVERIFY(buffer2);
    QImage buffer2Data = buffer2->data();
    QCOMPARE(buffer2Data, red);

    // while buffer2 is accessed we cannot access buffer1
    buffer1Data = buffer1->data();
    QVERIFY(buffer1Data.isNull());

    // a deep copy can be kept around
    QImage deepCopy = buffer2Data.copy();
    QCOMPARE(deepCopy, red);
    buffer2Data = QImage();
    QVERIFY(buffer2Data.isNull());
    QCOMPARE(deepCopy, red);

    // now that buffer2Data is destroyed we can access buffer1 again
    buffer1Data = buffer1->data();
    QVERIFY(!buffer1Data.isNull());
    QCOMPARE(buffer1Data, black);
}

void TestWaylandSurface::testOpaque()
{
    using namespace KWayland::Client;
    using namespace KWayland::Server;
    QSignalSpy serverSurfaceCreated(m_compositorInterface, SIGNAL(surfaceCreated(KWayland::Server::SurfaceInterface*)));
    QVERIFY(serverSurfaceCreated.isValid());
    Surface *s = m_compositor->createSurface();
    QVERIFY(serverSurfaceCreated.wait());
    SurfaceInterface *serverSurface = serverSurfaceCreated.first().first().value<KWayland::Server::SurfaceInterface*>();
    QVERIFY(serverSurface);
    QSignalSpy opaqueRegionChangedSpy(serverSurface, SIGNAL(opaqueChanged(QRegion)));
    QVERIFY(opaqueRegionChangedSpy.isValid());

    // by default there should be an empty opaque region
    QCOMPARE(serverSurface->opaque(), QRegion());

    // let's install an opaque region
    s->setOpaqueRegion(m_compositor->createRegion(QRegion(0, 10, 20, 30)).get());
    // the region should only be applied after the surface got committed
    wl_display_flush(m_connection->display());
    QCoreApplication::processEvents();
    QCOMPARE(serverSurface->opaque(), QRegion());
    QCOMPARE(opaqueRegionChangedSpy.count(), 0);

    // so let's commit to get the new region
    s->commit(Surface::CommitFlag::None);
    QVERIFY(opaqueRegionChangedSpy.wait());
    QCOMPARE(opaqueRegionChangedSpy.count(), 1);
    QCOMPARE(opaqueRegionChangedSpy.last().first().value<QRegion>(), QRegion(0, 10, 20, 30));
    QCOMPARE(serverSurface->opaque(), QRegion(0, 10, 20, 30));

    // committing without setting a new region shouldn't change
    s->commit(Surface::CommitFlag::None);
    wl_display_flush(m_connection->display());
    QCoreApplication::processEvents();
    QCOMPARE(opaqueRegionChangedSpy.count(), 1);
    QCOMPARE(serverSurface->opaque(), QRegion(0, 10, 20, 30));

    // let's change the opaque region
    s->setOpaqueRegion(m_compositor->createRegion(QRegion(10, 20, 30, 40)).get());
    s->commit(Surface::CommitFlag::None);
    QVERIFY(opaqueRegionChangedSpy.wait());
    QCOMPARE(opaqueRegionChangedSpy.count(), 2);
    QCOMPARE(opaqueRegionChangedSpy.last().first().value<QRegion>(), QRegion(10, 20, 30, 40));
    QCOMPARE(serverSurface->opaque(), QRegion(10, 20, 30, 40));

    // and let's go back to an empty region
    s->setOpaqueRegion();
    s->commit(Surface::CommitFlag::None);
    QVERIFY(opaqueRegionChangedSpy.wait());
    QCOMPARE(opaqueRegionChangedSpy.count(), 3);
    QCOMPARE(opaqueRegionChangedSpy.last().first().value<QRegion>(), QRegion());
    QCOMPARE(serverSurface->opaque(), QRegion());
}

void TestWaylandSurface::testInput()
{
    using namespace KWayland::Client;
    using namespace KWayland::Server;
    QSignalSpy serverSurfaceCreated(m_compositorInterface, SIGNAL(surfaceCreated(KWayland::Server::SurfaceInterface*)));
    QVERIFY(serverSurfaceCreated.isValid());
    Surface *s = m_compositor->createSurface();
    QVERIFY(serverSurfaceCreated.wait());
    SurfaceInterface *serverSurface = serverSurfaceCreated.first().first().value<KWayland::Server::SurfaceInterface*>();
    QVERIFY(serverSurface);
    QSignalSpy inputRegionChangedSpy(serverSurface, SIGNAL(inputChanged(QRegion)));
    QVERIFY(inputRegionChangedSpy.isValid());

    // by default there should be an empty == infinite input region
    QCOMPARE(serverSurface->input(), QRegion());
    QCOMPARE(serverSurface->inputIsInfinite(), true);

    // let's install an input region
    s->setInputRegion(m_compositor->createRegion(QRegion(0, 10, 20, 30)).get());
    // the region should only be applied after the surface got committed
    wl_display_flush(m_connection->display());
    QCoreApplication::processEvents();
    QCOMPARE(serverSurface->input(), QRegion());
    QCOMPARE(serverSurface->inputIsInfinite(), true);
    QCOMPARE(inputRegionChangedSpy.count(), 0);

    // so let's commit to get the new region
    s->commit(Surface::CommitFlag::None);
    QVERIFY(inputRegionChangedSpy.wait());
    QCOMPARE(inputRegionChangedSpy.count(), 1);
    QCOMPARE(inputRegionChangedSpy.last().first().value<QRegion>(), QRegion(0, 10, 20, 30));
    QCOMPARE(serverSurface->input(), QRegion(0, 10, 20, 30));
    QCOMPARE(serverSurface->inputIsInfinite(), false);

    // committing without setting a new region shouldn't change
    s->commit(Surface::CommitFlag::None);
    wl_display_flush(m_connection->display());
    QCoreApplication::processEvents();
    QCOMPARE(inputRegionChangedSpy.count(), 1);
    QCOMPARE(serverSurface->input(), QRegion(0, 10, 20, 30));
    QCOMPARE(serverSurface->inputIsInfinite(), false);

    // let's change the input region
    s->setInputRegion(m_compositor->createRegion(QRegion(10, 20, 30, 40)).get());
    s->commit(Surface::CommitFlag::None);
    QVERIFY(inputRegionChangedSpy.wait());
    QCOMPARE(inputRegionChangedSpy.count(), 2);
    QCOMPARE(inputRegionChangedSpy.last().first().value<QRegion>(), QRegion(10, 20, 30, 40));
    QCOMPARE(serverSurface->input(), QRegion(10, 20, 30, 40));
    QCOMPARE(serverSurface->inputIsInfinite(), false);

    // and let's go back to an empty region
    s->setInputRegion();
    s->commit(Surface::CommitFlag::None);
    QVERIFY(inputRegionChangedSpy.wait());
    QCOMPARE(inputRegionChangedSpy.count(), 3);
    QCOMPARE(inputRegionChangedSpy.last().first().value<QRegion>(), QRegion());
    QCOMPARE(serverSurface->input(), QRegion());
    QCOMPARE(serverSurface->inputIsInfinite(), true);
}

void TestWaylandSurface::testScale()
{
    // this test verifies that updating the scale factor is correctly passed to the Wayland server
    using namespace KWayland::Client;
    using namespace KWayland::Server;
    // create surface
    QSignalSpy serverSurfaceCreated(m_compositorInterface, &CompositorInterface::surfaceCreated);
    QVERIFY(serverSurfaceCreated.isValid());
    QScopedPointer<Surface> s(m_compositor->createSurface());
    QCOMPARE(s->scale(), 1);
    QVERIFY(serverSurfaceCreated.wait());
    SurfaceInterface *serverSurface = serverSurfaceCreated.first().first().value<KWayland::Server::SurfaceInterface*>();
    QVERIFY(serverSurface);
    QCOMPARE(serverSurface->scale(), 1);

    // let's change the scale factor
    QSignalSpy scaleChangedSpy(serverSurface, &SurfaceInterface::scaleChanged);

    //changing the scale implicitly changes the size
    QSignalSpy sizeChangedSpy(serverSurface, &SurfaceInterface::sizeChanged);

    QVERIFY(scaleChangedSpy.isValid());
    s->setScale(2);
    QCOMPARE(s->scale(), 2);
    // needs a commit
    QVERIFY(!scaleChangedSpy.wait(100));
    s->commit(Surface::CommitFlag::None);
    QVERIFY(scaleChangedSpy.wait());
    QCOMPARE(scaleChangedSpy.count(), 1);
    QCOMPARE(scaleChangedSpy.first().first().toInt(), 2);
    QCOMPARE(serverSurface->scale(), 2);

    //even though we've changed the scale, if we don't have a buffer we
    //don't have a size. If we don't have a size it can't have changed
    QCOMPARE(sizeChangedSpy.count(), 0);
    QVERIFY(!serverSurface->size().isValid());

    // let's try changing to same factor, should not emit changed on server
    s->setScale(2);
    s->commit(Surface::CommitFlag::None);
    QVERIFY(!scaleChangedSpy.wait(100));

    // but changing to a different value should still work
    s->setScale(4);
    s->commit(Surface::CommitFlag::None);
    QVERIFY(scaleChangedSpy.wait());
    QCOMPARE(scaleChangedSpy.count(), 2);
    QCOMPARE(scaleChangedSpy.first().first().toInt(), 2);
    QCOMPARE(scaleChangedSpy.last().first().toInt(), 4);
    QCOMPARE(serverSurface->scale(), 4);
    scaleChangedSpy.clear();

    //attach a buffer of 100x100, our scale is 4, so this should be a size of 25x25
    QImage red(100, 100, QImage::Format_ARGB32_Premultiplied);
    red.fill(QColor(255, 0, 0, 128));
    auto redBuffer = m_shm->createBuffer(red);
    s->attachBuffer(redBuffer.data());
    s->damage(QRect(0,0, 25,25));
    s->commit(Surface::CommitFlag::None);
    QVERIFY(sizeChangedSpy.wait());
    QCOMPARE(sizeChangedSpy.count(), 1);
    QCOMPARE(serverSurface->size(), QSize(25,25));
    sizeChangedSpy.clear();
    scaleChangedSpy.clear();

    //set the scale to 1, buffer is still 100x100 so size should change to 100x100
    s->setScale(1);
    s->commit(Surface::CommitFlag::None);
    QVERIFY(sizeChangedSpy.wait());
    QCOMPARE(sizeChangedSpy.count(), 1);
    QCOMPARE(scaleChangedSpy.count(), 1);
    QCOMPARE(serverSurface->scale(), 1);
    QCOMPARE(serverSurface->size(), QSize(100,100));
    sizeChangedSpy.clear();
    scaleChangedSpy.clear();

    //set scale and size in one commit, buffer is 50x50 at scale 2 so size should be 25x25
    QImage blue(50, 50, QImage::Format_ARGB32_Premultiplied);
    red.fill(QColor(255, 0, 0, 128));
    auto blueBuffer = m_shm->createBuffer(blue);
    s->attachBuffer(blueBuffer.data());
    s->setScale(2);
    s->commit(Surface::CommitFlag::None);
    QVERIFY(sizeChangedSpy.wait());
    QCOMPARE(sizeChangedSpy.count(), 1);
    QCOMPARE(scaleChangedSpy.count(), 1);
    QCOMPARE(serverSurface->scale(), 2);
    QCOMPARE(serverSurface->size(), QSize(25,25));
}

void TestWaylandSurface::testDestroy()
{
    using namespace KWayland::Client;
    Surface *s = m_compositor->createSurface();

    connect(m_connection, &ConnectionThread::connectionDied, s, &Surface::destroy);
    connect(m_connection, &ConnectionThread::connectionDied, m_compositor, &Compositor::destroy);
    connect(m_connection, &ConnectionThread::connectionDied, m_shm, &ShmPool::destroy);
    connect(m_connection, &ConnectionThread::connectionDied, m_queue, &EventQueue::destroy);
    QVERIFY(s->isValid());

    QSignalSpy connectionDiedSpy(m_connection, SIGNAL(connectionDied()));
    QVERIFY(connectionDiedSpy.isValid());
    delete m_display;
    m_display = nullptr;
    m_compositorInterface = nullptr;
    QVERIFY(connectionDiedSpy.wait());

    // now the Surface should be destroyed;
    QVERIFY(!s->isValid());

    // calling destroy again should not fail
    s->destroy();
}

void TestWaylandSurface::testUnmapOfNotMappedSurface()
{
    // this test verifies that a surface which doesn't have a buffer attached doesn't trigger the unmapped signal
    using namespace KWayland::Client;
    using namespace KWayland::Server;
    // create surface
    QSignalSpy serverSurfaceCreated(m_compositorInterface, &CompositorInterface::surfaceCreated);
    QVERIFY(serverSurfaceCreated.isValid());
    QScopedPointer<Surface> s(m_compositor->createSurface());
    QVERIFY(serverSurfaceCreated.wait());
    SurfaceInterface *serverSurface = serverSurfaceCreated.first().first().value<KWayland::Server::SurfaceInterface*>();

    QSignalSpy unmappedSpy(serverSurface, &SurfaceInterface::unmapped);
    QVERIFY(unmappedSpy.isValid());
    QSignalSpy scaleChanged(serverSurface, &SurfaceInterface::scaleChanged);

    // let's map a null buffer and change scale to trigger a signal we can wait for
    s->attachBuffer(Buffer::Ptr());
    s->setScale(2);
    s->commit(Surface::CommitFlag::None);

    QVERIFY(scaleChanged.wait());
    QVERIFY(unmappedSpy.isEmpty());
}

void TestWaylandSurface::testDamageTracking()
{
    // this tests the damage tracking feature
    using namespace KWayland::Client;
    using namespace KWayland::Server;
    // create surface
    QSignalSpy serverSurfaceCreated(m_compositorInterface, &CompositorInterface::surfaceCreated);
    QVERIFY(serverSurfaceCreated.isValid());
    QScopedPointer<Surface> s(m_compositor->createSurface());
    QVERIFY(serverSurfaceCreated.wait());
    SurfaceInterface *serverSurface = serverSurfaceCreated.first().first().value<KWayland::Server::SurfaceInterface*>();

    // before first commit, the tracked damage should be empty
    QVERIFY(serverSurface->trackedDamage().isEmpty());

    // Now let's damage the surface
    QSignalSpy damagedSpy(serverSurface, &SurfaceInterface::damaged);
    QImage image(QSize(100, 100), QImage::Format_ARGB32_Premultiplied);
    image.fill(Qt::red);
    s->attachBuffer(m_shm->createBuffer(image));
    s->damage(QRect(0, 0, 100, 100));
    s->commit(Surface::CommitFlag::None);
    QVERIFY(damagedSpy.wait());
    QCOMPARE(serverSurface->trackedDamage(), QRegion(0, 0, 100, 100));
    QCOMPARE(serverSurface->damage(), QRegion(0, 0, 100, 100));

    // resetting the tracked damage should empty it
    serverSurface->resetTrackedDamage();
    QVERIFY(serverSurface->trackedDamage().isEmpty());
    // but not affect the actual damage
    QCOMPARE(serverSurface->damage(), QRegion(0, 0, 100, 100));

    // let's damage some parts of the surface
    QPainter p;
    p.begin(&image);
    p.fillRect(QRect(0, 0, 10, 10), Qt::blue);
    p.end();
    s->attachBuffer(m_shm->createBuffer(image));
    s->damage(QRect(0, 0, 10, 10));
    s->commit(Surface::CommitFlag::None);
    QVERIFY(damagedSpy.wait());
    QCOMPARE(serverSurface->trackedDamage(), QRegion(0, 0, 10, 10));
    QCOMPARE(serverSurface->damage(), QRegion(0, 0, 10, 10));

    // and damage some part completely not bounding to the current damage region
    p.begin(&image);
    p.fillRect(QRect(50, 40, 20, 30), Qt::blue);
    p.end();
    s->attachBuffer(m_shm->createBuffer(image));
    s->damage(QRect(50, 40, 20, 30));
    s->commit(Surface::CommitFlag::None);
    QVERIFY(damagedSpy.wait());
    QCOMPARE(serverSurface->trackedDamage(), QRegion(0, 0, 10, 10).united(QRegion(50, 40, 20, 30)));
    QCOMPARE(serverSurface->trackedDamage().rectCount(), 2);
    QCOMPARE(serverSurface->damage(), QRegion(50, 40, 20, 30));

    // now let's reset the tracked damage again
    serverSurface->resetTrackedDamage();
    QVERIFY(serverSurface->trackedDamage().isEmpty());
    // but not affect the actual damage
    QCOMPARE(serverSurface->damage(), QRegion(50, 40, 20, 30));
}

void TestWaylandSurface::testSurfaceAt()
{
    // this test verifies that surfaceAt(const QPointF&) works as expected for the case of no children
    using namespace KWayland::Client;
    using namespace KWayland::Server;
    // create surface
    QSignalSpy serverSurfaceCreated(m_compositorInterface, &CompositorInterface::surfaceCreated);
    QVERIFY(serverSurfaceCreated.isValid());
    QScopedPointer<Surface> s(m_compositor->createSurface());
    QVERIFY(serverSurfaceCreated.wait());
    SurfaceInterface *serverSurface = serverSurfaceCreated.first().first().value<KWayland::Server::SurfaceInterface*>();

    // a newly created surface should not be mapped and not provide a surface at a position
    QVERIFY(!serverSurface->isMapped());
    QVERIFY(!serverSurface->surfaceAt(QPointF(0, 0)));

    // let's damage this surface
    QSignalSpy sizeChangedSpy(serverSurface, &SurfaceInterface::sizeChanged);
    QVERIFY(sizeChangedSpy.isValid());
    QImage image(QSize(100, 100), QImage::Format_ARGB32_Premultiplied);
    image.fill(Qt::red);
    s->attachBuffer(m_shm->createBuffer(image));
    s->damage(QRect(0, 0, 100, 100));
    s->commit(Surface::CommitFlag::None);
    QVERIFY(sizeChangedSpy.wait());

    // now the surface is mapped and surfaceAt should give the surface
    QVERIFY(serverSurface->isMapped());
    QCOMPARE(serverSurface->surfaceAt(QPointF(0, 0)), serverSurface);
    QCOMPARE(serverSurface->surfaceAt(QPointF(100, 100)), serverSurface);
    // outside the geometry it should not give a surface
    QVERIFY(!serverSurface->surfaceAt(QPointF(101, 101)));
    QVERIFY(!serverSurface->surfaceAt(QPointF(-1, -1)));
}

void TestWaylandSurface::testDestroyAttachedBuffer()
{
    // this test verifies that destroying of a buffer attached to a surface works
    using namespace KWayland::Client;
    using namespace KWayland::Server;
    // create surface
    QSignalSpy serverSurfaceCreated(m_compositorInterface, &CompositorInterface::surfaceCreated);
    QVERIFY(serverSurfaceCreated.isValid());
    QScopedPointer<Surface> s(m_compositor->createSurface());
    QVERIFY(serverSurfaceCreated.wait());
    SurfaceInterface *serverSurface = serverSurfaceCreated.first().first().value<KWayland::Server::SurfaceInterface*>();

    // let's damage this surface
    QSignalSpy damagedSpy(serverSurface, &SurfaceInterface::damaged);
    QVERIFY(damagedSpy.isValid());
    QImage image(QSize(100, 100), QImage::Format_ARGB32_Premultiplied);
    image.fill(Qt::red);
    s->attachBuffer(m_shm->createBuffer(image));
    s->damage(QRect(0, 0, 100, 100));
    s->commit(Surface::CommitFlag::None);
    QVERIFY(damagedSpy.wait());
    QVERIFY(serverSurface->buffer());

    // attach another buffer
    image.fill(Qt::blue);
    s->attachBuffer(m_shm->createBuffer(image));
    m_connection->flush();

    // Let's try to destroy it
    QSignalSpy destroySpy(serverSurface->buffer(), &BufferInterface::aboutToBeDestroyed);
    QVERIFY(destroySpy.isValid());
    delete m_shm;
    m_shm = nullptr;
    QVERIFY(destroySpy.wait());

    // TODO: should this emit unmapped?
    QVERIFY(!serverSurface->buffer());
}


void TestWaylandSurface::testDestroyWithPendingCallback()
{
    // this test tries to verify that destroying a surface with a pending callback works correctly
    // first create surface
    using namespace KWayland::Client;
    using namespace KWayland::Server;
    QScopedPointer<Surface> s(m_compositor->createSurface());
    QVERIFY(!s.isNull());
    QVERIFY(s->isValid());
    QSignalSpy surfaceCreatedSpy(m_compositorInterface, &CompositorInterface::surfaceCreated);
    QVERIFY(surfaceCreatedSpy.isValid());
    QVERIFY(surfaceCreatedSpy.wait());
    auto serverSurface = surfaceCreatedSpy.first().first().value<SurfaceInterface*>();
    QVERIFY(serverSurface);

    // now render to it
    QImage img(QSize(10, 10), QImage::Format_ARGB32_Premultiplied);
    img.fill(Qt::black);
    auto b = m_shm->createBuffer(img);
    s->attachBuffer(b);
    s->damage(QRect(0, 0, 10, 10));
    // add some frame callbacks
    for (int i = 0; i < 1000; i++) {
        wl_surface_frame(*s);
    }
    s->commit(KWayland::Client::Surface::CommitFlag::FrameCallback);
    QSignalSpy damagedSpy(serverSurface, &SurfaceInterface::damaged);
    QVERIFY(damagedSpy.isValid());
    QVERIFY(damagedSpy.wait());

    // now try to destroy the Surface again
    QSignalSpy destroyedSpy(serverSurface, &QObject::destroyed);
    QVERIFY(destroyedSpy.isValid());
    s.reset();
    QVERIFY(destroyedSpy.wait());
}

void TestWaylandSurface::testDisconnect()
{
    // this test verifies that the server side correctly tears down the resources when the client disconnects
    using namespace KWayland::Client;
    using namespace KWayland::Server;
    QScopedPointer<Surface> s(m_compositor->createSurface());
    QVERIFY(!s.isNull());
    QVERIFY(s->isValid());
    QSignalSpy surfaceCreatedSpy(m_compositorInterface, &CompositorInterface::surfaceCreated);
    QVERIFY(surfaceCreatedSpy.isValid());
    QVERIFY(surfaceCreatedSpy.wait());
    auto serverSurface = surfaceCreatedSpy.first().first().value<SurfaceInterface*>();
    QVERIFY(serverSurface);

    // destroy client
    QSignalSpy clientDisconnectedSpy(serverSurface->client(), &ClientConnection::disconnected);
    QVERIFY(clientDisconnectedSpy.isValid());
    QSignalSpy surfaceDestroyedSpy(serverSurface, &QObject::destroyed);
    QVERIFY(surfaceDestroyedSpy.isValid());
    if (m_connection) {
        m_connection->deleteLater();
        m_connection = nullptr;
    }
    QVERIFY(clientDisconnectedSpy.wait());
    QCOMPARE(clientDisconnectedSpy.count(), 1);
    if (surfaceDestroyedSpy.isEmpty()) {
        QVERIFY(surfaceDestroyedSpy.wait());
    }
    QTRY_COMPARE(surfaceDestroyedSpy.count(), 1);

    s->destroy();
    m_shm->destroy();
    m_compositor->destroy();
    m_queue->destroy();
}

void TestWaylandSurface::testOutput()
{
    // This test verifies that the enter/leave are sent correctly to the Client
    using namespace KWayland::Client;
    using namespace KWayland::Server;
    qRegisterMetaType<KWayland::Client::Output*>();
    QScopedPointer<Surface> s(m_compositor->createSurface());
    QVERIFY(!s.isNull());
    QVERIFY(s->isValid());
    QVERIFY(s->outputs().isEmpty());
    QSignalSpy enteredSpy(s.data(), &Surface::outputEntered);
    QVERIFY(enteredSpy.isValid());
    QSignalSpy leftSpy(s.data(), &Surface::outputLeft);
    QVERIFY(leftSpy.isValid());
    // wait for the surface on the Server side
    QSignalSpy surfaceCreatedSpy(m_compositorInterface, &CompositorInterface::surfaceCreated);
    QVERIFY(surfaceCreatedSpy.isValid());
    QVERIFY(surfaceCreatedSpy.wait());
    auto serverSurface = surfaceCreatedSpy.first().first().value<SurfaceInterface*>();
    QVERIFY(serverSurface);
    QCOMPARE(serverSurface->outputs(), QVector<OutputInterface*>());

    // create another registry to get notified about added outputs
    Registry registry;
    registry.setEventQueue(m_queue);
    QSignalSpy allAnnounced(&registry, &Registry::interfacesAnnounced);
    QVERIFY(allAnnounced.isValid());
    registry.create(m_connection);
    QVERIFY(registry.isValid());
    registry.setup();
    QVERIFY(allAnnounced.wait());
    QSignalSpy outputAnnouncedSpy(&registry, &Registry::outputAnnounced);
    QVERIFY(outputAnnouncedSpy.isValid());

    auto serverOutput = m_display->createOutput(m_display);
    serverOutput->create();
    QVERIFY(outputAnnouncedSpy.wait());
    QScopedPointer<Output> clientOutput(registry.createOutput(outputAnnouncedSpy.first().first().value<quint32>(), outputAnnouncedSpy.first().last().value<quint32>()));
    QVERIFY(clientOutput->isValid());
    m_connection->flush();
    m_display->dispatchEvents();

    // now enter it
    serverSurface->setOutputs(QVector<OutputInterface*>{serverOutput});
    QCOMPARE(serverSurface->outputs(), QVector<OutputInterface*>{serverOutput});
    QVERIFY(enteredSpy.wait());
    QCOMPARE(enteredSpy.count(), 1);
    QCOMPARE(enteredSpy.first().first().value<Output*>(), clientOutput.data());
    QCOMPARE(s->outputs(), QVector<Output*>{clientOutput.data()});

    // adding to same should not trigger
    serverSurface->setOutputs(QVector<OutputInterface*>{serverOutput});

    // leave again
    serverSurface->setOutputs(QVector<OutputInterface*>());
    QCOMPARE(serverSurface->outputs(), QVector<OutputInterface*>());
    QVERIFY(leftSpy.wait());
    QCOMPARE(enteredSpy.count(), 1);
    QCOMPARE(leftSpy.count(), 1);
    QCOMPARE(leftSpy.first().first().value<Output*>(), clientOutput.data());
    QCOMPARE(s->outputs(), QVector<Output*>());

    // leave again should not trigger
    serverSurface->setOutputs(QVector<OutputInterface*>());

    // and enter again, just to verify
    serverSurface->setOutputs(QVector<OutputInterface*>{serverOutput});
    QCOMPARE(serverSurface->outputs(), QVector<OutputInterface*>{serverOutput});
    QVERIFY(enteredSpy.wait());
    QCOMPARE(enteredSpy.count(), 2);
    QCOMPARE(leftSpy.count(), 1);

    //delete output client is on.
    //client should get an exit and be left on no outputs (which is allowed)
    serverOutput->deleteLater();
    QVERIFY(leftSpy.wait());
    QCOMPARE(serverSurface->outputs(), QVector<OutputInterface*>());
}

QTEST_GUILESS_MAIN(TestWaylandSurface)
#include "test_wayland_surface.moc"