Don't crash via proxy model when moving QModelIndexes

The layoutAboutToBeChanged signal gives proxies a chance to
persist QModelIndexes. The d->itemsAboutToBeMoved method is part of
the process of moving the persistent indexes. d->itemsAboutToBeMoved
must be called after layoutAboutToBeChanged. Otherwise persistent indexes
will not be updated.

Merge-request: 2219
Reviewed-by: Olivier Goffart <ogoffart@trolltech.com>

2 files changed, 22 insertions, 1 deletions

diff --git a/src/corelib/kernel/qabstractitemmodel.cpp b/src/corelib/kernel/qabstractitemmodel.cpp
index 10a61ca..9335085 100644
--- a/src/corelib/kernel/qabstractitemmodel.cpp
+++ b/src/corelib/kernel/qabstractitemmodel.cpp
@@ -2546,9 +2546,9 @@ bool QAbstractItemModel::beginMoveRows(const QModelIndex &sourceParent, int sour
     int destinationLast = destinationChild + (sourceLast - sourceFirst);
     d->changes.push(QAbstractItemModelPrivate::Change(destinationParent, destinationChild, destinationLast));
 
-    d->itemsAboutToBeMoved(sourceParent, sourceFirst, sourceLast, destinationParent, destinationChild, Qt::Vertical);
     emit rowsAboutToBeMoved(sourceParent, sourceFirst, sourceLast, destinationParent, destinationChild);
     emit layoutAboutToBeChanged();
+    d->itemsAboutToBeMoved(sourceParent, sourceFirst, sourceLast, destinationParent, destinationChild, Qt::Vertical);
     return true;
 }
 
diff --git a/tests/auto/qabstractitemmodel/tst_qabstractitemmodel.cpp b/tests/auto/qabstractitemmodel/tst_qabstractitemmodel.cpp
index 413419d..3736813 100644
--- a/tests/auto/qabstractitemmodel/tst_qabstractitemmodel.cpp
+++ b/tests/auto/qabstractitemmodel/tst_qabstractitemmodel.cpp
@@ -112,6 +112,8 @@ private slots:
     void testMoveWithinOwnRange_data();
     void testMoveWithinOwnRange();
 
+    void testMoveThroughProxy();
+
     void testReset();
 
 
@@ -1112,6 +1114,25 @@ void tst_QAbstractItemModel::testMoveSameParentUp()
     }
 }
 
+void tst_QAbstractItemModel::testMoveThroughProxy()
+{
+    QSortFilterProxyModel *proxy = new QSortFilterProxyModel(this);
+    proxy->setSourceModel(m_model);
+
+    QList<QPersistentModelIndex> persistentList;
+
+    persistentList.append(proxy->index(0, 0));
+    persistentList.append(proxy->index(0, 0, proxy->mapFromSource(m_model->index(5, 0))));
+
+    ModelMoveCommand *moveCommand = new ModelMoveCommand(m_model, this);
+    moveCommand->setNumCols(4);
+    moveCommand->setAncestorRowNumbers(QList<int>() << 5);
+    moveCommand->setStartRow(0);
+    moveCommand->setEndRow(0);
+    moveCommand->setDestRow(0);
+    moveCommand->doCommand();
+}
+
 void tst_QAbstractItemModel::testMoveToGrandParent_data()
 {
     QTest::addColumn<int>("startRow");