Mock a trait with a fluent interface

[neugepower]

I try to configure a mock factory which is implemented as fluent interface:

#[cfg_attr(test, mocked)]
pub trait IdFactory {
    fn with_value(&mut self, value: usize) -> &mut dyn IdFactory;
    fn build(&mut self) -> Box<dyn Id>;
}

My code under test:

...
let id = id_factory.with_id(0).build();
...

And my expectations:

...
let (id_factory_mock, id_factory_mock_handle) = scenario.create_mock_for::<dyn IdFactory>();
scenario.expect(id_factory_mock_handle.with_value(0).and_return(XXX));
...

For the XXX part I don't now what to return. I tried several things but I'm not sure if it is even possible at all right now. I thought of sth. like this:

scenario.expect(id_factory_mock_handle.with_value(0).then().build().and_return(Box::new(MyId)));

[kriomant]

I'm working on it. It's not so easy to do it without breaking things.