Get Access to Mockall Mocks that are used by the tested code inside of an Arc

Question

I am trying to test code in rust using Mocks from the mockall crate.

    #[automock]
    trait MyTrait {
        fn some_func(&self) -> i64;
    }
    
    
    struct MyStruct {
        data: Arc<dyn MyTrait>
    }
    
    impl MyStruct {
    
        // ... lots of code
    }
    
    #[test]
    fn a_test() {
        let mut mock = MockMyTrait::new();
        mock.expect_some_func().return_const(42);
        let testee = MyStruct { data: Arc::new(mock) };
    
        // test a lot of code from MyStruct
    
        // here I want to call 'mock.chekcpoint()' and setup more expectations
    
        // test some more MyStruct code
    }

Since the mock is now moved into the Arc I do not know how I can access the checkpoint method of the mock object. Is there a way to get access to the Mock object or is there a better way for me to structure my code to make testing easier/possible ?