Fixes: Use QRect::isEmpty() rather than isNull() if possible.

RevBy:    Andreas
Details:  Note that isNull() implies isEmpty(), but it only catches
          the cases where width and height is 0.
(cherry picked from commit 8a2ebc96220f50be3a9c382c32d7eaab89921ff7)

3 files changed, 7 insertions, 7 deletions

diff --git a/src/gui/graphicsview/qgraphicsitem.cpp b/src/gui/graphicsview/qgraphicsitem.cpp
index 4787b6c..e300628 100644
--- a/src/gui/graphicsview/qgraphicsitem.cpp
+++ b/src/gui/graphicsview/qgraphicsitem.cpp
@@ -3757,7 +3757,7 @@ bool QGraphicsItemPrivate::isProxyWidget() const
 */
 void QGraphicsItem::update(const QRectF &rect)
 {
-    if (d_ptr->dirty)
+    if (d_ptr->dirty || (rect.isEmpty() && !rect.isNull()))
         return;
     if (d_ptr->scene && isVisible()) {
         if (CacheMode(d_ptr->cacheMode) != NoCache) {
diff --git a/src/gui/graphicsview/qgraphicsscene.cpp b/src/gui/graphicsview/qgraphicsscene.cpp
index 96710a4..0a53f7f 100644
--- a/src/gui/graphicsview/qgraphicsscene.cpp
+++ b/src/gui/graphicsview/qgraphicsscene.cpp
@@ -3474,7 +3474,7 @@ QVariant QGraphicsScene::inputMethodQuery(Qt::InputMethodQuery query) const
 void QGraphicsScene::update(const QRectF &rect)
 {
     Q_D(QGraphicsScene);
-    if (d->updateAll)
+    if (d->updateAll || (rect.isEmpty() && !rect.isNull()))
         return;
 
     // Check if anyone's connected; if not, we can send updates directly to
diff --git a/src/gui/graphicsview/qgraphicsview.cpp b/src/gui/graphicsview/qgraphicsview.cpp
index 0e4d5be..686f95c 100644
--- a/src/gui/graphicsview/qgraphicsview.cpp
+++ b/src/gui/graphicsview/qgraphicsview.cpp
@@ -862,7 +862,7 @@ void QGraphicsViewPrivate::_q_updateLaterSlot()
     dirtyRectCount += dirtyRects.size();
 
     bool noUpdate = !fullUpdatePending && viewportUpdateMode == QGraphicsView::FullViewportUpdate;
-    if ((dirtyRectCount > 0 || !dirtyBoundingRect.isNull()) && !fullUpdatePending && !noUpdate) {
+    if ((dirtyRectCount > 0 || !dirtyBoundingRect.isEmpty()) && !fullUpdatePending && !noUpdate) {
         if (viewportUpdateMode == QGraphicsView::BoundingRectViewportUpdate
             || (viewportUpdateMode == QGraphicsView::SmartViewportUpdate
                 && dirtyRectCount >= QGRAPHICSVIEW_REGION_RECT_THRESHOLD)) {
@@ -3284,7 +3284,7 @@ void QGraphicsView::mouseMoveEvent(QMouseEvent *event)
             }
 
             // Update old rubberband
-            if (d->viewportUpdateMode != QGraphicsView::NoViewportUpdate && !d->rubberBandRect.isNull()) {
+            if (d->viewportUpdateMode != QGraphicsView::NoViewportUpdate && !d->rubberBandRect.isEmpty()) {
                 if (d->viewportUpdateMode != FullViewportUpdate)
                     viewport()->update(d->rubberBandRegion(viewport(), d->rubberBandRect));
                 else
@@ -3466,7 +3466,7 @@ void QGraphicsView::paintEvent(QPaintEvent *event)
     QPainter painter(viewport());
     QTransform original = painter.worldTransform();
 #ifndef QT_NO_RUBBERBAND
-    if (d->rubberBanding && !d->rubberBandRect.isNull())
+    if (d->rubberBanding && !d->rubberBandRect.isEmpty())
         painter.save();
 #endif
     // Set up render hints
@@ -3561,7 +3561,7 @@ void QGraphicsView::paintEvent(QPaintEvent *event)
 
 #ifndef QT_NO_RUBBERBAND
     // Rubberband
-    if (d->rubberBanding && !d->rubberBandRect.isNull()) {
+    if (d->rubberBanding && !d->rubberBandRect.isEmpty()) {
         painter.restore();
         QStyleOptionRubberBand option;
         option.initFrom(viewport());
@@ -3645,7 +3645,7 @@ void QGraphicsView::scrollContentsBy(int dx, int dy)
 
 #ifndef QT_NO_RUBBERBAND
     // Update old rubberband
-    if (d->viewportUpdateMode != QGraphicsView::NoViewportUpdate && !d->rubberBandRect.isNull()) {
+    if (d->viewportUpdateMode != QGraphicsView::NoViewportUpdate && !d->rubberBandRect.isEmpty()) {
         if (d->viewportUpdateMode != FullViewportUpdate)
             viewport()->update(d->rubberBandRegion(viewport(), d->rubberBandRect));
         else