Fixes crash when destroying a QGraphicsItem.

When clearing the focus on an item, the focus was previously passed to
the closest parent focus scope (if any). But the focus should go to the
closest parent focus scope only if the item being cleared of the focus
is itself a focus scope. This incorrect behavior leaded to invalid
pointers in QGraphicsItem under specific circumstances, eventually
leading to a crash when destroying the item.

Auto-test included.

Task-number: QT-2649
Reviewed-by: Andreas Aardal Hanssen

1 files changed, 57 insertions, 0 deletions

diff --git a/tests/auto/qgraphicsitem/tst_qgraphicsitem.cpp b/tests/auto/qgraphicsitem/tst_qgraphicsitem.cpp
index 7c1b97e..269ec24 100644
--- a/tests/auto/qgraphicsitem/tst_qgraphicsitem.cpp
+++ b/tests/auto/qgraphicsitem/tst_qgraphicsitem.cpp
@@ -438,6 +438,7 @@ private slots:
     void QTBUG_6738_missingUpdateWithSetParent();
     void QTBUG_7714_fullUpdateDiscardingOpacityUpdate2();
     void QT_2653_fullUpdateDiscardingOpacityUpdate();
+    void QT_2649_focusScope();
 
 private:
     QList<QGraphicsItem *> paintedItems;
@@ -10002,5 +10003,61 @@ void tst_QGraphicsItem::QTBUG_7714_fullUpdateDiscardingOpacityUpdate2()
     QTRY_COMPARE(view.repaints, 1);
 }
 
+void tst_QGraphicsItem::QT_2649_focusScope()
+{
+    QGraphicsScene *scene = new QGraphicsScene;
+
+    QGraphicsRectItem *subFocusItem = new QGraphicsRectItem;
+    subFocusItem->setFlags(QGraphicsItem::ItemIsFocusable);
+    subFocusItem->setFocus();
+    QCOMPARE(subFocusItem->focusItem(), (QGraphicsItem *)subFocusItem);
+
+    QGraphicsRectItem *scope = new QGraphicsRectItem;
+    scope->setFlags(QGraphicsItem::ItemIsFocusable | QGraphicsItem::ItemIsFocusScope);
+    scope->setFocus();
+    subFocusItem->setParentItem(scope);
+    QCOMPARE(subFocusItem->focusItem(), (QGraphicsItem *)subFocusItem);
+    QCOMPARE(subFocusItem->focusScopeItem(), (QGraphicsItem *)0);
+    QCOMPARE(scope->focusItem(), (QGraphicsItem *)subFocusItem);
+    QCOMPARE(scope->focusScopeItem(), (QGraphicsItem *)subFocusItem);
+
+    QGraphicsRectItem *rootItem = new QGraphicsRectItem;
+    rootItem->setFlags(QGraphicsItem::ItemIsFocusable);
+    scope->setParentItem(rootItem);
+    QCOMPARE(rootItem->focusItem(), (QGraphicsItem *)subFocusItem);
+    QCOMPARE(rootItem->focusScopeItem(), (QGraphicsItem *)0);
+    QCOMPARE(subFocusItem->focusItem(), (QGraphicsItem *)subFocusItem);
+    QCOMPARE(subFocusItem->focusScopeItem(), (QGraphicsItem *)0);
+    QCOMPARE(scope->focusItem(), (QGraphicsItem *)subFocusItem);
+    QCOMPARE(scope->focusScopeItem(), (QGraphicsItem *)subFocusItem);
+
+    scene->addItem(rootItem);
+
+    QEvent windowActivate(QEvent::WindowActivate);
+    qApp->sendEvent(scene, &windowActivate);
+    scene->setFocus();
+
+    QCOMPARE(rootItem->focusItem(), (QGraphicsItem *)subFocusItem);
+    QCOMPARE(scope->focusItem(), (QGraphicsItem *)subFocusItem);
+    QCOMPARE(subFocusItem->focusItem(), (QGraphicsItem *)subFocusItem);
+    QCOMPARE(rootItem->focusScopeItem(), (QGraphicsItem *)0);
+    QCOMPARE(scope->focusScopeItem(), (QGraphicsItem *)subFocusItem);
+    QCOMPARE(subFocusItem->focusScopeItem(), (QGraphicsItem *)0);
+    QVERIFY(subFocusItem->hasFocus());
+
+    //If we hide the focusScope, the entire subFocus chain should be cleared
+    scope->hide();
+
+    QCOMPARE(rootItem->focusItem(), (QGraphicsItem *)0);
+    QCOMPARE(scope->focusItem(), (QGraphicsItem *)0);
+    QCOMPARE(subFocusItem->focusItem(), (QGraphicsItem *)0);
+    QCOMPARE(rootItem->focusScopeItem(), (QGraphicsItem *)0);
+    QCOMPARE(scope->focusScopeItem(), (QGraphicsItem *)subFocusItem);
+    QCOMPARE(subFocusItem->focusScopeItem(), (QGraphicsItem *)0);
+    QVERIFY(!subFocusItem->hasFocus());
+
+    delete scene;
+}
+
 QTEST_MAIN(tst_QGraphicsItem)
 #include "tst_qgraphicsitem.moc"