Assume that I have a QML value type myPoint and another type myContainer that holds the points.
The myContainer class has a property points of type QVariantList, and for certain reasons I cannot change it to QList<Point>.

From the QML side, assigning a list<myPoint> to the property works. However, if I create a Q_INVOKABLE method that takes QVariantList and returns myContainer, passing the same list<myPoint> into it fails:

property list<myPoint> points: [ {x: 1, y: 2}, {x: 2, y: 1} ]

property myContainer c1: ({ points: root.points }) // works
property myContainer c2: Singleton.createContainer(points) // does not work :(

I attached the full project which exposes two value types and a singleton to QML and shows the inconsistent behavior. The debug output shows that in the second case the objects are wrapped in an extra QVariant