Test structuring in cargo workspace

help
1

I have a problem structuring my tests. In my cargo workspace there is a business crate, containing business logic and tests. Then I have a test_fixtures crate, providing mock implementations of business traits, to be used in the tests of the business crate as well as the tests of others crates (web, db, ...).

The test_fixtures crate depends on the business crate, while the business crate
dev-depends on the test_fixtures crate. This leads to compiler errors, telling me that I compiled business twice, with different configurations leading to type errors of types with the same name (one attached below).

So now I'm wondering how I can achieve sharing mocks between several crates. Before, I tried to put the mocks next to the business tests, but then the mocks are not visible in tests of the web and db crate, because when testing web, its dependencies are not compiled in the #[cfg(test)] configuration.

error[E0308]: mismatched types
    --> business/token_endpoint.rs:1227:9
     |
1222 |     async fn build_refresh_token(client_id: &str) -> EncodedRefreshToken {
     |                                                      ------------------- expected `token::EncodedRefreshToken` because of return type
...
1227 |         token_creator.finalize_refresh_token(token).unwrap()
     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `token::EncodedRefreshToken`, found `tiny_auth_business::token::EncodedRefreshToken`
     |
     = note: `tiny_auth_business::token::EncodedRefreshToken` and `token::EncodedRefreshToken` have similar names, but are actually distinct types
note: `tiny_auth_business::token::EncodedRefreshToken` is defined in crate `tiny_auth_business`
    --> /home/unicorn/Programs/tiny-auth/src/rust/business/token.rs:197:1
     |
197  | pub struct EncodedRefreshToken(String);
     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: `token::EncodedRefreshToken` is defined in the current crate
    --> business/token.rs:197:1
     |
197  | pub struct EncodedRefreshToken(String);
     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
     = note: the crate `tiny_auth_business` is compiled multiple times, possibly with different configurations
2

Thanks to this other discussion I now use integration tests for the relevant tests.