Rust digit_overflow

digit_overflow.rs

#[test]
fn digit_overflow() {
    assert_eq!(u16::MAX.wrapping_add(9), 8);
    assert_eq!(u16::MAX.saturating_add(9), u16::MAX);
    assert_eq!(u16::MAX.checked_add(9), None);
    assert_eq!(u16::MAX.overflowing_add(9), (8, true));
}

#[test]
fn digit_overflow_mul() {
    assert_eq!(u16::MAX.wrapping_mul(9), u16::MAX - 8);
    assert_eq!(u16::MAX.saturating_mul(9), u16::MAX);
    assert_eq!(u16::MAX.checked_mul(9), None);
    assert_eq!(u16::MAX.overflowing_mul(9), (u16::MAX - 8, true));
}