Fixes the gif plugin's rendering for some animated gif files.

In the case of optimized animated gifs, we don't want to discard
the contents of the previous frame, this is handled if needed in the
disposal process.

Task-number: 247365
Reviewed-by: Samuel

11 files changed, 24 insertions, 2 deletions

diff --git a/tests/auto/qimagereader/images/qt.gif b/tests/auto/qimagereader/images/qt.gif
new file mode 100644
index 0000000000..e0a5a80b13
--- /dev/null
+++ b/tests/auto/qimagereader/images/qt.gif
diff --git a/tests/auto/qimagereader/images/qt1.gif b/tests/auto/qimagereader/images/qt1.gif
new file mode 100644
index 0000000000..0ce910cee0
--- /dev/null
+++ b/tests/auto/qimagereader/images/qt1.gif
diff --git a/tests/auto/qimagereader/images/qt2.gif b/tests/auto/qimagereader/images/qt2.gif
new file mode 100644
index 0000000000..993a315d0f
--- /dev/null
+++ b/tests/auto/qimagereader/images/qt2.gif
diff --git a/tests/auto/qimagereader/images/qt3.gif b/tests/auto/qimagereader/images/qt3.gif
new file mode 100644
index 0000000000..7391678a99
--- /dev/null
+++ b/tests/auto/qimagereader/images/qt3.gif
diff --git a/tests/auto/qimagereader/images/qt4.gif b/tests/auto/qimagereader/images/qt4.gif
new file mode 100644
index 0000000000..41109a9c3f
--- /dev/null
+++ b/tests/auto/qimagereader/images/qt4.gif
diff --git a/tests/auto/qimagereader/images/qt5.gif b/tests/auto/qimagereader/images/qt5.gif
new file mode 100644
index 0000000000..5a3fb54ff5
--- /dev/null
+++ b/tests/auto/qimagereader/images/qt5.gif
diff --git a/tests/auto/qimagereader/images/qt6.gif b/tests/auto/qimagereader/images/qt6.gif
new file mode 100644
index 0000000000..f22e7c980a
--- /dev/null
+++ b/tests/auto/qimagereader/images/qt6.gif
diff --git a/tests/auto/qimagereader/images/qt7.gif b/tests/auto/qimagereader/images/qt7.gif
new file mode 100644
index 0000000000..a315671417
--- /dev/null
+++ b/tests/auto/qimagereader/images/qt7.gif
diff --git a/tests/auto/qimagereader/images/qt8.gif b/tests/auto/qimagereader/images/qt8.gif
new file mode 100644
index 0000000000..2a7d09e859
--- /dev/null
+++ b/tests/auto/qimagereader/images/qt8.gif
diff --git a/tests/auto/qimagereader/qimagereader.qrc b/tests/auto/qimagereader/qimagereader.qrc
index 13ce582acf..e3113c6d27 100644
--- a/tests/auto/qimagereader/qimagereader.qrc
+++ b/tests/auto/qimagereader/qimagereader.qrc
@@ -1,5 +1,5 @@
-<!DOCTYPE RCC><RCC version="1.0">
-    <qresource>
+<RCC>
+    <qresource prefix="/" >
         <file>images/16bpp.bmp</file>
         <file>images/4bpp-rle.bmp</file>
         <file>images/YCbCr_cmyk.jpg</file>
@@ -47,5 +47,14 @@
         <file>images/tst7.png</file>
         <file>images/transparent.xpm</file>
         <file>images/trolltech.gif</file>
+        <file>images/qt.gif</file>
+        <file>images/qt1.gif</file>
+        <file>images/qt2.gif</file>
+        <file>images/qt3.gif</file>
+        <file>images/qt4.gif</file>
+        <file>images/qt5.gif</file>
+        <file>images/qt6.gif</file>
+        <file>images/qt7.gif</file>
+        <file>images/qt8.gif</file>
     </qresource>
 </RCC>
diff --git a/tests/auto/qimagereader/tst_qimagereader.cpp b/tests/auto/qimagereader/tst_qimagereader.cpp
index 18900b4c68..1403280ef3 100644
--- a/tests/auto/qimagereader/tst_qimagereader.cpp
+++ b/tests/auto/qimagereader/tst_qimagereader.cpp
@@ -136,6 +136,7 @@ private slots:
 
 #if defined QTEST_HAVE_GIF
     void gifHandlerBugs();
+    void animatedGif();
 #endif
 
     void readCorruptImage_data();
@@ -671,6 +672,18 @@ void tst_QImageReader::gifHandlerBugs()
         QCOMPARE(im1.convertToFormat(QImage::Format_ARGB32), im2.convertToFormat(QImage::Format_ARGB32));
     }
 }
+
+void tst_QImageReader::animatedGif()
+{
+    QImageReader io(prefix + "qt.gif");
+    QImage image= io.read();
+    int i=0;
+    while(!image.isNull()){
+        QString frameName = QString(prefix + "qt%1.gif").arg(++i);
+        QCOMPARE(image, QImage(frameName));
+        image=io.read();
+    }
+}
 #endif
 
 class Server : public QObject