TEST(QPixmapCache, DemonstrateUnwantedCleanup)
{
    QPixmapCache::setCacheLimit(20*1024); //20 MB
    QPixmapCache::clear();
    {
        QPixmap p1(1000, 1000); //1000*1000*4 = 4 MB
        EXPECT_TRUE(QPixmapCache::insert("p1", p1));
        //p1 goes out of scope but should be copied in QPixmapCache
    }
    {
        QPixmap p2(1000, 1000); //1000*1000*4
        EXPECT_TRUE(QPixmapCache::insert("p2", p2));
        //p2 goes out of scope but should be copied in QPixmapCache
    }
    QPixmap p;
    EXPECT_TRUE(QPixmapCache::find("p1", p));
    EXPECT_TRUE(QPixmapCache::find("p2", p));
    //Wait till 30 seconds for QPMCache::flushDetachedPixmaps(false) to be called and drop something from the cache
    EXPECT_LT(QPixmapCache::totalUsed(), QPixmapCache::cacheLimit()/2); //less than half the cache is used
    const int iPixmapsInCache = QPixmapCache::allPixmaps().size();
    while (QPixmapCache::allPixmaps().size() >= iPixmapsInCache)
    {
        QCoreApplication::processEvents(QEventLoop::AllEvents, 50); //allow void QPMCache::timerEvent(QTimerEvent *) to be called
    }
    EXPECT_LT(QPixmapCache::totalUsed(), QPixmapCache::cacheLimit()/2); //less than half the cache is used
    EXPECT_FALSE(QPixmapCache::find("p1", p)); //somehow p1 got removed while there was still plenty of cache left, so why the cleanup ?
    EXPECT_TRUE(QPixmapCache::find("p2", p));
}