diff --git a/src/libcore/num/mod.rs b/src/libcore/num/mod.rs index aa4d4bc638b1d..a062fbda5bad0 100644 --- a/src/libcore/num/mod.rs +++ b/src/libcore/num/mod.rs @@ -1765,7 +1765,11 @@ assert_eq!((-a).mod_euc(-b), 1); pub fn mod_euc(self, rhs: Self) -> Self { let r = self % rhs; if r < 0 { - r + rhs.abs() + if rhs < 0 { + r - rhs + } else { + r + rhs + } } else { r } diff --git a/src/libcore/tests/lib.rs b/src/libcore/tests/lib.rs index 7d3852d2f2a98..ccf647c358d67 100644 --- a/src/libcore/tests/lib.rs +++ b/src/libcore/tests/lib.rs @@ -15,6 +15,7 @@ #![feature(core_private_diy_float)] #![feature(dec2flt)] #![feature(decode_utf8)] +#![feature(euclidean_division)] #![feature(exact_size_is_empty)] #![feature(fixed_size_array)] #![feature(float_internals)] diff --git a/src/libcore/tests/num/int_macros.rs b/src/libcore/tests/num/int_macros.rs index 8d791283ab87e..71d2e7945389b 100644 --- a/src/libcore/tests/num/int_macros.rs +++ b/src/libcore/tests/num/int_macros.rs @@ -30,6 +30,11 @@ mod tests { num::test_num(10 as $T, 2 as $T); } + #[test] + fn test_mod_euc() { + assert!((-1 as $T).mod_euc(MIN) == MAX); + } + #[test] pub fn test_abs() { assert!((1 as $T).abs() == 1 as $T);