Cargo also supports running tests and benchmarks. In-depth testing and benchmarking is covered in Chapter 3, Tests, Documentation, and Benchmarks. In this section, we will go over a brief introduction on how to run tests using Cargo. We'll write tests for a library crate. To work our way through this section, let's create a crate by running cargo new myexponent --lib:
A library crate is similar to a binary crate. The difference is that instead of src/main.rs and a main function inside as an entry point, we have src/lib.rs with a trivial test function, it_works, which is marked with a #[test] annotation. We can run ...
