How to suppress “function is never used” warning for a function used by tests?

Question

I\'m writing a program in Rust and I have some tests for it. I wrote a helper function for these tests, but whenever I build using cargo build it warns me that

Answer 1

dead_code is a lint, which means you can allow it on the thing that's causing it to trigger.

#[allow(dead_code)]
fn dummy() {}

fn main() {}