diff --git a/tests/auto/gui/image/qimage/tst_qimage.cpp b/tests/auto/gui/image/qimage/tst_qimage.cpp
index bb0bd672128..a7a20796670 100644
--- a/tests/auto/gui/image/qimage/tst_qimage.cpp
+++ b/tests/auto/gui/image/qimage/tst_qimage.cpp
@@ -265,89 +265,9 @@ private:
     const QString m_prefix;
 };
 
-static QLatin1String formatToString(QImage::Format format)
+static QByteArray formatToString(QImage::Format format)
 {
-    switch (format) {
-    case QImage::Format_Invalid:
-        return QLatin1String("Invalid");
-    case QImage::Format_Mono:
-        return QLatin1String("Mono");
-    case QImage::Format_MonoLSB:
-        return QLatin1String("MonoLSB");
-    case QImage::Format_Indexed8:
-        return QLatin1String("Indexed8");
-    case QImage::Format_RGB32:
-        return QLatin1String("RGB32");
-    case QImage::Format_ARGB32:
-        return QLatin1String("ARGB32");
-    case QImage::Format_ARGB32_Premultiplied:
-        return QLatin1String("ARGB32pm");
-    case QImage::Format_RGB16:
-        return QLatin1String("RGB16");
-    case QImage::Format_ARGB8565_Premultiplied:
-        return QLatin1String("ARGB8565pm");
-    case QImage::Format_RGB666:
-        return QLatin1String("RGB666");
-    case QImage::Format_ARGB6666_Premultiplied:
-        return QLatin1String("ARGB6666pm");
-    case QImage::Format_RGB555:
-        return QLatin1String("RGB555");
-    case QImage::Format_ARGB8555_Premultiplied:
-        return QLatin1String("ARGB8555pm");
-    case QImage::Format_RGB888:
-        return QLatin1String("RGB888");
-    case QImage::Format_RGB444:
-        return QLatin1String("RGB444");
-    case QImage::Format_ARGB4444_Premultiplied:
-        return QLatin1String("ARGB4444pm");
-    case QImage::Format_RGBX8888:
-        return QLatin1String("RGBx88888");
-    case QImage::Format_RGBA8888:
-        return QLatin1String("RGBA88888");
-    case QImage::Format_RGBA8888_Premultiplied:
-        return QLatin1String("RGBA88888pm");
-    case QImage::Format_BGR30:
-        return QLatin1String("BGR30");
-    case QImage::Format_A2BGR30_Premultiplied:
-        return QLatin1String("A2BGR30pm");
-    case QImage::Format_RGB30:
-        return QLatin1String("RGB30");
-    case QImage::Format_A2RGB30_Premultiplied:
-        return QLatin1String("A2RGB30pm");
-    case QImage::Format_Alpha8:
-        return QLatin1String("Alpha8");
-    case QImage::Format_Grayscale8:
-        return QLatin1String("Grayscale8");
-    case QImage::Format_RGBX64:
-        return QLatin1String("RGBx64");
-    case QImage::Format_RGBA64:
-        return QLatin1String("RGBA64");
-    case QImage::Format_RGBA64_Premultiplied:
-        return QLatin1String("RGBA64pm");
-    case QImage::Format_Grayscale16:
-        return QLatin1String("Grayscale16");
-    case QImage::Format_BGR888:
-        return QLatin1String("BGR888");
-    case QImage::Format_RGBX16FPx4:
-        return QLatin1String("RGBx16FPx4");
-    case QImage::Format_RGBA16FPx4:
-        return QLatin1String("RGBA16FPx4");
-    case QImage::Format_RGBA16FPx4_Premultiplied:
-        return QLatin1String("RGBA16FPx4pm");
-    case QImage::Format_RGBX32FPx4:
-        return QLatin1String("RGBx32FPx4");
-    case QImage::Format_RGBA32FPx4:
-        return QLatin1String("RGBA32FPx4");
-    case QImage::Format_RGBA32FPx4_Premultiplied:
-        return QLatin1String("RGBA32FPx4pm");
-    case QImage::Format_CMYK8888:
-        return QLatin1String("CMYK8888");
-    case QImage::NImageFormats:
-        break;
-    };
-    Q_UNREACHABLE();
-    qWarning("Unhandled image format");
-    return QLatin1String("unknown");
+    return QDebug::toBytes(format).mid(15);
 }
 
 tst_QImage::tst_QImage()
@@ -3159,7 +3079,7 @@ void tst_QImage::genericRgbConversion_data()
     for (int i = QImage::Format_RGB32; i < QImage::NImageFormats; ++i) {
         if (i == QImage::Format_Alpha8)
             continue;
-        const QLatin1String formatI = formatToString(QImage::Format(i));
+        const auto formatI = formatToString(QImage::Format(i));
         for (int j = QImage::Format_RGB32; j < QImage::NImageFormats; ++j) {
             if (j == QImage::Format_Alpha8)
                 continue;
@@ -3427,7 +3347,7 @@ void tst_QImage::colorSpaceRgbConversion_data()
     };
 
     for (auto fromFormat : formats) {
-        const QLatin1String formatI = formatToString(fromFormat);
+        const auto formatI = formatToString(fromFormat);
         for (auto toFormat : formats) {
             QTest::addRow("%s -> %s", formatI.data(), formatToString(toFormat).data())
                     << fromFormat << toFormat;