1use core::f64;
2
3use super::{copysign, trunc};
4
5#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
6pub fn round(x: f64) -> f64 {
7 trunc(x + copysign(0.5 - 0.25 * f64::EPSILON, x))
8}
9
10#[cfg(test)]
11mod tests {
12 use super::round;
13
14 #[test]
15 fn negative_zero() {
16 assert_eq!(round(-0.0_f64).to_bits(), (-0.0_f64).to_bits());
17 }
18
19 #[test]
20 fn sanity_check() {
21 assert_eq!(round(-1.0), -1.0);
22 assert_eq!(round(2.8), 3.0);
23 assert_eq!(round(-0.5), -1.0);
24 assert_eq!(round(0.5), 1.0);
25 assert_eq!(round(-1.5), -2.0);
26 assert_eq!(round(1.5), 2.0);
27 }
28}