QtQml: Correctly convert to QQmlListProperty<QObject>

If we have a QQmlListWrapper, we can extract its property.

Fixes: QTBUG-117829
Pick-to: 6.2
Change-Id: I46ae8db1aabf7c1b617a22f371ce4f060cf4bb38
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
(cherry picked from commit bb698b7f2e974a23b688dd15393f6a550448a5a8)
(cherry picked from commit 20fd12d7f569f8a4a6dfc6c7f0d5f270f4683e90)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

2 files changed, 15 insertions, 0 deletions

diff --git a/src/qml/jsruntime/qv4engine.cpp b/src/qml/jsruntime/qv4engine.cpp
index 0ef2b5db40..c9d8639816 100644
--- a/src/qml/jsruntime/qv4engine.cpp
+++ b/src/qml/jsruntime/qv4engine.cpp
@@ -2649,6 +2649,13 @@ bool ExecutionEngine::metaTypeFromJS(const Value &value, QMetaType metaType, voi
         }
     }
 
+    if (metaType == QMetaType::fromType<QQmlListProperty<QObject>>()) {
+        if (const QV4::QmlListWrapper *wrapper = value.as<QV4::QmlListWrapper>()) {
+            *reinterpret_cast<QQmlListProperty<QObject> *>(data) = wrapper->d()->property();
+            return true;
+        }
+    }
+
     if (const QQmlValueTypeWrapper *vtw = value.as<QQmlValueTypeWrapper>()) {
         const QMetaType valueType = vtw->type();
         if (valueType == metaType)
diff --git a/tests/auto/qml/qjsengine/tst_qjsengine.cpp b/tests/auto/qml/qjsengine/tst_qjsengine.cpp
index c7ed1cf4ef..f08a3dbcaf 100644
--- a/tests/auto/qml/qjsengine/tst_qjsengine.cpp
+++ b/tests/auto/qml/qjsengine/tst_qjsengine.cpp
@@ -17,6 +17,7 @@
 #include <QScopeGuard>
 #include <QUrl>
 #include <QModelIndex>
+#include <QtQml/qqmllist.h>
 
 #ifdef Q_CC_MSVC
 #define NO_INLINE __declspec(noinline)
@@ -1703,6 +1704,13 @@ void tst_QJSEngine::valueConversion_basic()
         QCOMPARE(eng.fromScriptValue<QChar>(eng.toScriptValue(c)), c);
     }
 
+    {
+        QList<QObject *> list = {this};
+        QQmlListProperty<QObject> prop(this, &list);
+        QJSValue jsVal = eng.toScriptValue(prop);
+        QCOMPARE(eng.fromScriptValue<QQmlListProperty<QObject>>(jsVal), prop);
+    }
+
     QVERIFY(eng.toScriptValue(static_cast<void *>(nullptr)).isNull());
 }