Fix emission of QQmlListModel::rowsAboutToBeXxx() signals

Call beginInsertRows(), beginMoveRows() and beginRemoveRows() before
the change to ensure that rowsAboutToBeInserted(), rowsAboutToBeMoved()
and rowsAboutToBeRemoved() get emitted before the change as appropriate.

NOTE: This patch solves the problem for the most common use case, when
ListModel is used without WorkerScript. QQmlListModelWorkerAgent needs
similar changes in order to fix the signals when ListModel is used with
WorkerScript (QTBUG-39321).

Task-number: QTBUG-39279
Change-Id: Idec5167d70b242f6f7d8b7cff008e130afc62505
Reviewed-by: Alan Alpert <aalpert@blackberry.com>

1 files changed, 129 insertions, 0 deletions

diff --git a/tests/auto/qml/qqmllistmodel/tst_qqmllistmodel.cpp b/tests/auto/qml/qqmllistmodel/tst_qqmllistmodel.cpp
index 9b57eeffa9..b37f0e3d26 100644
--- a/tests/auto/qml/qqmllistmodel/tst_qqmllistmodel.cpp
+++ b/tests/auto/qml/qqmllistmodel/tst_qqmllistmodel.cpp
@@ -132,6 +132,7 @@ private slots:
     void empty_element_warning_data();
     void datetime();
     void datetime_data();
+    void about_to_be_signals();
 };
 
 bool tst_qqmllistmodel::compareVariantList(const QVariantList &testList, QVariant object)
@@ -1306,6 +1307,134 @@ void tst_qqmllistmodel::datetime()
     QVERIFY(expected == dtResult);
 }
 
+class RowTester : public QObject
+{
+    Q_OBJECT
+public:
+    RowTester(QAbstractItemModel *model) : QObject(model), model(model)
+    {
+        reset();
+        connect(model, SIGNAL(rowsAboutToBeInserted(QModelIndex,int,int)), this, SLOT(rowsAboutToBeInserted()));
+        connect(model, SIGNAL(rowsInserted(QModelIndex,int,int)), this, SLOT(rowsInserted()));
+        connect(model, SIGNAL(rowsAboutToBeRemoved(QModelIndex,int,int)), this, SLOT(rowsAboutToBeRemoved()));
+        connect(model, SIGNAL(rowsRemoved(QModelIndex,int,int)), this, SLOT(rowsRemoved()));
+        connect(model, SIGNAL(rowsAboutToBeMoved(QModelIndex,int,int,QModelIndex,int)), this, SLOT(rowsAboutToBeMoved()));
+        connect(model, SIGNAL(rowsMoved(QModelIndex,int,int,QModelIndex,int)), this, SLOT(rowsMoved()));
+    }
+
+    void reset()
+    {
+        rowsAboutToBeInsertedCalls = 0;
+        rowsAboutToBeInsertedCount = 0;
+        rowsInsertedCalls = 0;
+        rowsInsertedCount = 0;
+        rowsAboutToBeRemovedCalls = 0;
+        rowsAboutToBeRemovedCount = 0;
+        rowsRemovedCalls = 0;
+        rowsRemovedCount = 0;
+        rowsAboutToBeMovedCalls = 0;
+        rowsAboutToBeMovedData.clear();
+        rowsMovedCalls = 0;
+        rowsMovedData.clear();
+    }
+
+    int rowsAboutToBeInsertedCalls;
+    int rowsAboutToBeInsertedCount;
+    int rowsInsertedCalls;
+    int rowsInsertedCount;
+    int rowsAboutToBeRemovedCalls;
+    int rowsAboutToBeRemovedCount;
+    int rowsRemovedCalls;
+    int rowsRemovedCount;
+    int rowsAboutToBeMovedCalls;
+    QVariantList rowsAboutToBeMovedData;
+    int rowsMovedCalls;
+    QVariantList rowsMovedData;
+
+private slots:
+    void rowsAboutToBeInserted()
+    {
+        rowsAboutToBeInsertedCalls++;
+        rowsAboutToBeInsertedCount = model->rowCount();
+    }
+
+    void rowsInserted()
+    {
+        rowsInsertedCalls++;
+        rowsInsertedCount = model->rowCount();
+    }
+
+    void rowsAboutToBeRemoved()
+    {
+        rowsAboutToBeRemovedCalls++;
+        rowsAboutToBeRemovedCount = model->rowCount();
+    }
+
+    void rowsRemoved()
+    {
+        rowsRemovedCalls++;
+        rowsRemovedCount = model->rowCount();
+    }
+
+    void rowsAboutToBeMoved()
+    {
+        rowsAboutToBeMovedCalls++;
+        for (int i = 0; i < model->rowCount(); ++i)
+            rowsAboutToBeMovedData += model->data(model->index(i, 0), 0);
+    }
+
+    void rowsMoved()
+    {
+        rowsMovedCalls++;
+        for (int i = 0; i < model->rowCount(); ++i)
+            rowsMovedData += model->data(model->index(i, 0), 0);
+    }
+
+private:
+    QAbstractItemModel *model;
+};
+
+void tst_qqmllistmodel::about_to_be_signals()
+{
+    QQmlEngine engine;
+    QQmlListModel model;
+    QQmlEngine::setContextForObject(&model,engine.rootContext());
+
+    RowTester tester(&model);
+
+    QQmlExpression e1(engine.rootContext(), &model, "{append({'test':0})}");
+    e1.evaluate();
+
+    QCOMPARE(tester.rowsAboutToBeInsertedCalls, 1);
+    QCOMPARE(tester.rowsAboutToBeInsertedCount, 0);
+    QCOMPARE(tester.rowsInsertedCalls, 1);
+    QCOMPARE(tester.rowsInsertedCount, 1);
+
+    QQmlExpression e2(engine.rootContext(), &model, "{append({'test':1})}");
+    e2.evaluate();
+
+    QCOMPARE(tester.rowsAboutToBeInsertedCalls, 2);
+    QCOMPARE(tester.rowsAboutToBeInsertedCount, 1);
+    QCOMPARE(tester.rowsInsertedCalls, 2);
+    QCOMPARE(tester.rowsInsertedCount, 2);
+
+    QQmlExpression e3(engine.rootContext(), &model, "{move(0, 1, 1)}");
+    e3.evaluate();
+
+    QCOMPARE(tester.rowsAboutToBeMovedCalls, 1);
+    QCOMPARE(tester.rowsAboutToBeMovedData, QVariantList() << 0.0 << 1.0);
+    QCOMPARE(tester.rowsMovedCalls, 1);
+    QCOMPARE(tester.rowsMovedData, QVariantList() << 1.0 << 0.0);
+
+    QQmlExpression e4(engine.rootContext(), &model, "{remove(0, 2)}");
+    e4.evaluate();
+
+    QCOMPARE(tester.rowsAboutToBeRemovedCalls, 1);
+    QCOMPARE(tester.rowsAboutToBeRemovedCount, 2);
+    QCOMPARE(tester.rowsRemovedCalls, 1);
+    QCOMPARE(tester.rowsRemovedCount, 0);
+}
+
 QTEST_MAIN(tst_qqmllistmodel)
 
 #include "tst_qqmllistmodel.moc"