Ensure raster pixmap cache key is the same as that of pixmap.toImage()

This is done to support texture uploads in an image provider. It ensures
we can load the texture using QImage in the image provider, and when
it is later painted as a pixmap, the cacheKey will be identical
(assuming no format conversion was required).

Change-Id: I54229511ed91ce5430cc478af5aff0d96685a2da
Reviewed-by: Gunnar Sletta <gunnar.sletta@digia.com>

1 files changed, 23 insertions, 0 deletions

diff --git a/tests/auto/gui/image/qpixmap/tst_qpixmap.cpp b/tests/auto/gui/image/qpixmap/tst_qpixmap.cpp
index 576519e2ca..e204da059d 100644
--- a/tests/auto/gui/image/qpixmap/tst_qpixmap.cpp
+++ b/tests/auto/gui/image/qpixmap/tst_qpixmap.cpp
@@ -114,6 +114,7 @@ private slots:
 
     void convertFromImageNoDetach();
     void convertFromImageDetach();
+    void convertFromImageCacheKey();
 
 #if defined(Q_OS_WIN)
     void toWinHBITMAP_data();
@@ -779,6 +780,28 @@ void tst_QPixmap::convertFromImageDetach()
     QVERIFY(copy.isDetached());
 }
 
+void tst_QPixmap::convertFromImageCacheKey()
+{
+    QPixmap randomPixmap(10, 10);
+    if (randomPixmap.handle()->classId() != QPlatformPixmap::RasterClass)
+        QSKIP("Test only valid for raster pixmaps");
+
+    //first get the screen format
+    QImage::Format screenFormat = randomPixmap.toImage().format();
+    QVERIFY(screenFormat != QImage::Format_Invalid);
+
+    QImage orig(100,100, screenFormat);
+    orig.fill(0);
+
+    QPixmap pix = QPixmap::fromImage(orig);
+    QImage copy = pix.toImage();
+
+    QVERIFY(copy.format() == screenFormat);
+
+    QCOMPARE(orig.cacheKey(), pix.cacheKey());
+    QCOMPARE(copy.cacheKey(), pix.cacheKey());
+}
+
 #if defined(Q_OS_WIN)
 
 QT_BEGIN_NAMESPACE