Injecting static types

[antimora]

Injecting static types

[la10736]

Sorry, but I'm not sure to have understood your question. Do you want to write some tests and apply them on the 2 backends?

Something like the follow code?

trait MyTrait {
    fn get() -> u32;
}

struct A;
struct B;

impl MyTrait for A {
    fn get() -> u32 {
        42
    }
}

impl MyTrait for B {
    fn get() -> u32 {
        84
    }
}

use rstest::rstest;
use std::marker::PhantomData;

#[rstest]
#[case(PhantomData::<A>)]
#[case(PhantomData::<B>)]
fn test_get<T: MyTrait>(#[case] _a: PhantomData<T>) {
    assert_eq!(T::get() % 2, 0);
}

You can also use rstest_reuse to spread these cases to some tests.

[antimora]

@a10736, thank you so much for you suggestion and great examples. rstest_reuse is a great pointer. I didn't know about it.

Continuing with your example, let me clarify.

Basically, I need to have MyTrait and the unit tests defined in crate "MyTraitAndTests". And the trait implementations in "ImplA" and "ImplB" crates, which will consume the unit tests defined in "MyTraitAndTests". It would very convenient when I import the unit tests, I can pass type A (that implements MyTrait) to a whole suit without referencing individual methods. It seems rstest_reuse supports such use case, correct?

[la10736]

Maybe what you need are contract tests. There's a nice way to implement contract tests that's just work for integration tests.

Look at [email protected]:la10736/contract_tests_example.git and let me know if it's what you're looking for. The nice thing here if that is the tests itself that ask for the implementation to use and you import the module with the tests for each dependency that you would tests. Is a sort of Dependency Injection.

[antimora]

@la10736 Thank you. I will look into this. Here is the link that takes directly to the repo: https://github.com/la10736/contract_tests_example

[antimora]

Maybe what you need are contract tests. There's a nice way to implement contract tests that's just work for integration tests.

Look at [email protected]:la10736/contract_tests_example.git and let me know if it's what you're looking for. The nice thing here if that is the tests itself that ask for the implementation to use and you import the module with the tests for each dependency that you would tests. Is a sort of Dependency Injection.

I will check it out and report back. Thank you.