| use super::copysign; |
| use super::trunc; |
| use core::f64; |
| |
| #[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)] |
| pub fn round(x: f64) -> f64 { |
| trunc(x + copysign(0.5 - 0.25 * f64::EPSILON, x)) |
| } |
| |
| #[cfg(test)] |
| mod tests { |
| use super::round; |
| |
| #[test] |
| fn negative_zero() { |
| assert_eq!(round(-0.0_f64).to_bits(), (-0.0_f64).to_bits()); |
| } |
| |
| #[test] |
| fn sanity_check() { |
| assert_eq!(round(-1.0), -1.0); |
| assert_eq!(round(2.8), 3.0); |
| assert_eq!(round(-0.5), -1.0); |
| assert_eq!(round(0.5), 1.0); |
| assert_eq!(round(-1.5), -2.0); |
| assert_eq!(round(1.5), 2.0); |
| } |
| } |