QFileSystemModel need to better case insensitivity support

#include <QApplication>
#include <QFileSystemModel>
#include <QListView>
#include <QHBoxLayout>
#include <QDir>
#include <QDebug>
#include <QTimer>

class Widget : public QWidget
{
    Q_OBJECT

public:
    Widget()
        :fileModel(new QFileSystemModel),fileView(new QListView)
    {
        QFile fileForTest("AaaBbbCcc.Dat");
        fileForTest.open(QFile::WriteOnly);
        fileForTest.close();

        fileModel->setRootPath(QDir::currentPath());
        fileView->setModel(fileModel);
        fileView->setRootIndex(fileModel->index(QDir::currentPath()));

        QHBoxLayout *box = new QHBoxLayout(this);
        box->addWidget(fileView);

        QTimer::singleShot(100, this, SLOT(output()));
    }

private slots:
    void output()
    {
        int idx0 = fileModel->index("AaaBbbCcc.Dat").row();
        int idx1 = fileModel->index("aaabbbccc.dat").row();
        int idx2 = fileModel->index("AAABBBCCC.DAT").row();

        qDebug()<<idx0<<idx1<<idx2;
    }

private:
    QFileSystemModel *fileModel;
    QListView *fileView;
};

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    Widget w;
    w.show();
    
    return a.exec();
}

#include "main.moc"