How to use lib in test directory which is outside of src in rust?

Question

I have a following folder structure,

.
├── utils/
│   ├── helpers.rs
│   └── lib.rs
├── tests/
│   └── helpers.rs
└── Cargo.toml

lib.rs just includes helpers.rs ,

mod helpers;

So how do use utils::helpers inside tests/helpers.rs ?

Answer 1

The tests folder contains your integration tests. Those tests may only use the public interface of your library, and not test internals that are hidden to a user of your library.

If you want your users to use utils::helpers , then make sure that it is pub lic and write integration tests from the downstream developers perspective. However, if you only want to write unit tests (which is much more likely), then add them in the helpers module itself.

See "Test Organization" in The Rust Programming Language for more information.