env_cargo_path

env_cargo_path

What it does

Checks for env! or option_env! applied outside of a test to a Cargo environment variable containing a path, e.g., CARGO_MANIFEST_DIR.

Why is this bad?

The path might not exist when the code is used in production.

Known problems

The lint does not apply inside macro arguments. So false negatives could result.

Example

fn main() {
    let path = option_env!("CARGO");
    println!("{:?}", path);
}

Use instead:

fn main() {
    let path = std::env::var("CARGO");
    println!("{:?}", path);
}