Validar CPF Rust lang

utils.rs

/// Valida CPF
/// Espera um `&str` no formato: "52998224725"
pub fn validate_cpf(cpf: &str) -> bool {
    let all_digits_repeated = [cpf.chars().nth(0).unwrap()]
        .repeat(11)
        .into_iter()
        .collect::<String>();

    if cpf.len() != 11 || cpf == &*all_digits_repeated {
        return false;
    };

    let mut first_sum = 0;
    let mut second_sum = 0;

    for (idx, number) in cpf.chars().map(|d| d.to_digit(10).unwrap()).enumerate() {
        second_sum += number * (11 - idx as u32);
        if idx == 9 {
            break;
        };
        first_sum += number * (10 - idx as u32);
    }

    let first_validator = cpf.chars().nth(9).and_then(|d| d.to_digit(10)).unwrap();
    let second_validator = cpf.chars().nth(10).and_then(|d| d.to_digit(10)).unwrap();

    if first_sum * 10 % 11 != first_validator {
        return false;
    }
    if second_sum * 10 % 11 != second_validator {
        return false;
    }

    true
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn t_cpf_valid_validator() {
        let res = validate_cpf("52998224725");
        assert!(res);
    }

    #[test]
    fn t_cpf_invalid_validator() {
        let res = validate_cpf("11111111111");
        assert!(!res);
    }