How do I use mockall in a struct that derives Clone?

[augustocdias]

So I have a struct like this

#[derive(Clone)]
pub struct MyStruct {
...
}

#[automock]
impl MyStruct{
}

I use the double macro in the imports to not conflict the namespacing. But my tests fail to compile because it says the MockMyStruct crate does not implement Clone. Is there a way to achieve what I'm trying here?

And the function I wanna test at some point calls clone on this object and passes to another function. Is there a way to verify calls in this "cloned" object?

[asomers]

The way you specified it, Mockall doesn't know that MyStruct is supposed to be Clone. Instead, do it like this:

mock! {
    MyStruct {}
    impl Clone for MyStruct {
        fn clone(&self) -> Self;
    }
}

[augustocdias]

I tried that, but then I have to add every method from my struct into the mock! and the double stops working so I can't pass this new mock to my function

[asomers]

#[double] should still work, if you structure your modules correctly.

[augustocdias]

So I have in the structs module the following

#[derive(Clone)]
pub struct MyStruct {
}

#[automock]
impl MyStruct{
   pub fn my_func() {}
}

Then I have a function in another module:

#[double]
use my_mod::MyStruct;

fn function_i_wanna_test(my_struct: MyStruct) -> Result<(), Error> {}

I have a separate test module where I write my unit tests

use my_mod::MyStructMock;

mock !{
   MyStruct {
         pub fn my_func();
   }
   impl Clone for MyStruct {
        fn clone(&self) -> Self;
    }
}

#[test]
fn test_my_struct() {
  let mock = MyStructMock::default();
  function_i_wanna_test(mock);
}

This doesn't compile... How should I change then to make it work?

[asomers]

What is MyStructMock? I don't see a definition for that anywhere. And why are you using both automock and mock!? You should use only one. Do it like this:

pub mod my_mod {
    #[derive(Clone)]
    pub struct MyStruct {
    }

    impl MyStruct{
       pub fn my_func() {}
    }
    mock !{
       MyStruct {
             pub fn my_func();
       }
       impl Clone for MyStruct {
            fn clone(&self) -> Self;
        }
    }
}
mod test {
    #[double]
    use super::my_mod::MyStruct;
    ...
}

[augustocdias]

Sorry, it is MockMyStruct. It is the name generated by mockall.

I was not using the #[double] in the tests. Which I'll start to use because it looks better :)

Your suggestion works. Thanks for the help