#[cfg(test)]
mod tests {
    #[test]
    fn is_valid_os() {
        let etc = "/etc";
        let result: bool = std::path::Path::new(etc).is_dir();

        assert_eq!(result, true);
    }

    #[test]
    fn basic_arithmetic_works() {
        let result = 2 + 2;

        assert_eq!(result, 4);
    }
}