use std::time::Duration;
pub trait SaturatingArithmetic<T> {
fn sol_saturating_add(&self, rhs: Self) -> Self;
fn sol_saturating_sub(&self, rhs: Self) -> Self;
fn sol_saturating_mul(&self, rhs: T) -> Self;
}
impl SaturatingArithmetic<u32> for Duration {
fn sol_saturating_add(&self, rhs: Self) -> Self {
self.checked_add(rhs)
.unwrap_or_else(|| Self::new(u64::MAX, 1_000_000_000u32.saturating_sub(1)))
}
fn sol_saturating_sub(&self, rhs: Self) -> Self {
self.checked_sub(rhs).unwrap_or_else(|| Self::new(0, 0))
}
fn sol_saturating_mul(&self, rhs: u32) -> Self {
self.checked_mul(rhs)
.unwrap_or_else(|| Self::new(u64::MAX, 1_000_000_000u32.saturating_sub(1)))
}
}
#[cfg(test)]
pub mod tests {
use super::*;
#[test]
fn test_duration() {
let empty_duration = Duration::new(0, 0);
let max_duration = Duration::new(u64::MAX, 1_000_000_000 - 1);
let duration = Duration::new(u64::MAX, 0);
let add = duration.sol_saturating_add(duration);
assert_eq!(add, max_duration);
let sub = duration.sol_saturating_sub(max_duration);
assert_eq!(sub, empty_duration);
let mult = duration.sol_saturating_mul(u32::MAX);
assert_eq!(mult, max_duration);
}
}