QmlModels: Make model object properties non-FINAL again

You can override them from your model after all. The anonymous
properties can be final, though. They're impossible to override.

Amends commit 2af5cc0a7f62680f41e83f32d2ecac502db5c1e7.

Pick-to: 6.7 6.6
Fixes: QTBUG-120499
Change-Id: Ib251f8a1845366074faec2db4914855c04b4db34
Reviewed-by: Olivier De Cannière <olivier.decanniere@qt.io>
Reviewed-by: Vladimir Belyavsky <belyavskyv@gmail.com>
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

2 files changed, 84 insertions, 0 deletions

diff --git a/tests/auto/qml/qqmldelegatemodel/data/overriddenModelData.qml b/tests/auto/qml/qqmldelegatemodel/data/overriddenModelData.qml
new file mode 100644
index 0000000000..e392b2e5c9
--- /dev/null
+++ b/tests/auto/qml/qqmldelegatemodel/data/overriddenModelData.qml
@@ -0,0 +1,55 @@
+import QtQml
+
+DelegateModel {
+    id: root
+
+    property ListModel listModel: ListModel {
+        ListElement {
+            modelData: "a"
+            row: "b"
+            column: "c"
+            model: "d"
+            hasModelChildren: "e"
+            index: "f"
+        }
+    }
+
+    property var array: [{
+        modelData: "a",
+        row: "b",
+        column: "c",
+        model: "d",
+        hasModelChildren: "e",
+        index: "f"
+    }]
+
+    property QtObject object: QtObject {
+        property string modelData: "a"
+        property string row: "b"
+        property string column: "c"
+        property string model: "d"
+        property string hasModelChildren: "e"
+        property string index: "f"
+    }
+
+    property int n: -1
+
+    model: {
+        switch (n) {
+        case 0: return listModel
+        case 1: return array
+        case 2: return object
+        }
+        return undefined;
+    }
+
+    delegate: QtObject {
+        required property string modelData
+        required property string row
+        required property string column
+        required property string model
+        required property string hasModelChildren
+        required property string index
+        objectName: [modelData, row, column, model, hasModelChildren, index].join(" ")
+    }
+}
diff --git a/tests/auto/qml/qqmldelegatemodel/tst_qqmldelegatemodel.cpp b/tests/auto/qml/qqmldelegatemodel/tst_qqmldelegatemodel.cpp
index c3b184e869..e3fa762b25 100644
--- a/tests/auto/qml/qqmldelegatemodel/tst_qqmldelegatemodel.cpp
+++ b/tests/auto/qml/qqmldelegatemodel/tst_qqmldelegatemodel.cpp
@@ -35,6 +35,7 @@ private slots:
     void universalModelData();
     void typedModelData();
     void requiredModelData();
+    void overriddenModelData();
     void deleteRace();
     void persistedItemsStayInCache();
     void unknownContainersAsModel();
@@ -474,6 +475,34 @@ void tst_QQmlDelegateModel::requiredModelData()
     }
 }
 
+void tst_QQmlDelegateModel::overriddenModelData()
+{
+    QTest::failOnWarning(QRegularExpression(
+            "Final member [^ ]+ is overridden in class [^\\.]+. The override won't be used."));
+
+    QQmlEngine engine;
+    QQmlComponent c(&engine, testFileUrl("overriddenModelData.qml"));
+    QVERIFY2(c.isReady(), qPrintable(c.errorString()));
+    QScopedPointer<QObject> o(c.create());
+
+    QQmlDelegateModel *delegateModel = qobject_cast<QQmlDelegateModel *>(o.data());
+    QVERIFY(delegateModel);
+
+    for (int i = 0; i < 3; ++i) {
+        delegateModel->setProperty("n", i);
+        QObject *delegate = delegateModel->object(0);
+        QVERIFY(delegate);
+
+        if (i == 2) {
+            // Someone is certainly relying on this.
+            // We need to find a migration mechanism to fix it.
+            QEXPECT_FAIL("", "You can actually not override if the model is a QObject", Continue);
+        }
+
+        QCOMPARE(delegate->objectName(), QLatin1String("a b c d e f"));
+    }
+}
+
 void tst_QQmlDelegateModel::deleteRace()
 {
     QQmlEngine engine;