[QTBUG-27420] Make Q{Box,Grid,Form}Layout::takeAt() unparent a nested layout

QStackedLayout doesn't have support for QLayout, only QWidget, so
the issue doesn't arise there.

Reported-by: Johannes Schaub
Task-number: QTBUG-27420

Change-Id: I71f8d10a036918c16d8f8c9197a2ec61cd76cf01
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>

1 files changed, 24 insertions, 0 deletions

diff --git a/tests/auto/widgets/kernel/qgridlayout/tst_qgridlayout.cpp b/tests/auto/widgets/kernel/qgridlayout/tst_qgridlayout.cpp
index 34b38c1e53..e52ff3fa8b 100644
--- a/tests/auto/widgets/kernel/qgridlayout/tst_qgridlayout.cpp
+++ b/tests/auto/widgets/kernel/qgridlayout/tst_qgridlayout.cpp
@@ -52,6 +52,7 @@
 #include <QtWidgets/QLineEdit>
 #include <QtWidgets/QRadioButton>
 #include <QStyleFactory>
+#include <QSharedPointer>
 
 class tst_QGridLayout : public QObject
 {
@@ -89,6 +90,8 @@ private slots:
     void contentsRect();
     void distributeMultiCell();
 
+    void taskQTBUG_27420_takeAtShouldUnparentLayout();
+
 private:
     QWidget *testWidget;
     QGridLayout *testLayout;
@@ -1605,5 +1608,26 @@ void tst_QGridLayout::distributeMultiCell()
     QCOMPARE(w.sizeHint().height(), 11 + 57 + 11);
 }
 
+void tst_QGridLayout::taskQTBUG_27420_takeAtShouldUnparentLayout()
+{
+    QSharedPointer<QGridLayout> outer(new QGridLayout);
+    QPointer<QGridLayout> inner = new QGridLayout;
+
+    outer->addLayout(inner, 0, 0);
+    QCOMPARE(outer->count(), 1);
+    QCOMPARE(inner->parent(), outer.data());
+
+    QLayoutItem *item = outer->takeAt(0);
+    QCOMPARE(item->layout(), inner.data());
+    QVERIFY(!item->layout()->parent());
+
+    outer.reset();
+
+    if (inner)
+        delete item; // success: a taken item/layout should not be deleted when the old parent is deleted
+    else
+        QVERIFY(!inner.isNull());
+}
+
 QTEST_MAIN(tst_QGridLayout)
 #include "tst_qgridlayout.moc"