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-rw-r--r--vendor/num-traits/src/ops/saturating.rs130
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diff --git a/vendor/num-traits/src/ops/saturating.rs b/vendor/num-traits/src/ops/saturating.rs
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+use core::ops::{Add, Mul, Sub};
+
+/// Saturating math operations. Deprecated, use `SaturatingAdd`, `SaturatingSub` and
+/// `SaturatingMul` instead.
+pub trait Saturating {
+ /// Saturating addition operator.
+ /// Returns a+b, saturating at the numeric bounds instead of overflowing.
+ fn saturating_add(self, v: Self) -> Self;
+
+ /// Saturating subtraction operator.
+ /// Returns a-b, saturating at the numeric bounds instead of overflowing.
+ fn saturating_sub(self, v: Self) -> Self;
+}
+
+macro_rules! deprecated_saturating_impl {
+ ($trait_name:ident for $($t:ty)*) => {$(
+ impl $trait_name for $t {
+ #[inline]
+ fn saturating_add(self, v: Self) -> Self {
+ Self::saturating_add(self, v)
+ }
+
+ #[inline]
+ fn saturating_sub(self, v: Self) -> Self {
+ Self::saturating_sub(self, v)
+ }
+ }
+ )*}
+}
+
+deprecated_saturating_impl!(Saturating for isize i8 i16 i32 i64 i128);
+deprecated_saturating_impl!(Saturating for usize u8 u16 u32 u64 u128);
+
+macro_rules! saturating_impl {
+ ($trait_name:ident, $method:ident, $t:ty) => {
+ impl $trait_name for $t {
+ #[inline]
+ fn $method(&self, v: &Self) -> Self {
+ <$t>::$method(*self, *v)
+ }
+ }
+ };
+}
+
+/// Performs addition that saturates at the numeric bounds instead of overflowing.
+pub trait SaturatingAdd: Sized + Add<Self, Output = Self> {
+ /// Saturating addition. Computes `self + other`, saturating at the relevant high or low boundary of
+ /// the type.
+ fn saturating_add(&self, v: &Self) -> Self;
+}
+
+saturating_impl!(SaturatingAdd, saturating_add, u8);
+saturating_impl!(SaturatingAdd, saturating_add, u16);
+saturating_impl!(SaturatingAdd, saturating_add, u32);
+saturating_impl!(SaturatingAdd, saturating_add, u64);
+saturating_impl!(SaturatingAdd, saturating_add, usize);
+saturating_impl!(SaturatingAdd, saturating_add, u128);
+
+saturating_impl!(SaturatingAdd, saturating_add, i8);
+saturating_impl!(SaturatingAdd, saturating_add, i16);
+saturating_impl!(SaturatingAdd, saturating_add, i32);
+saturating_impl!(SaturatingAdd, saturating_add, i64);
+saturating_impl!(SaturatingAdd, saturating_add, isize);
+saturating_impl!(SaturatingAdd, saturating_add, i128);
+
+/// Performs subtraction that saturates at the numeric bounds instead of overflowing.
+pub trait SaturatingSub: Sized + Sub<Self, Output = Self> {
+ /// Saturating subtraction. Computes `self - other`, saturating at the relevant high or low boundary of
+ /// the type.
+ fn saturating_sub(&self, v: &Self) -> Self;
+}
+
+saturating_impl!(SaturatingSub, saturating_sub, u8);
+saturating_impl!(SaturatingSub, saturating_sub, u16);
+saturating_impl!(SaturatingSub, saturating_sub, u32);
+saturating_impl!(SaturatingSub, saturating_sub, u64);
+saturating_impl!(SaturatingSub, saturating_sub, usize);
+saturating_impl!(SaturatingSub, saturating_sub, u128);
+
+saturating_impl!(SaturatingSub, saturating_sub, i8);
+saturating_impl!(SaturatingSub, saturating_sub, i16);
+saturating_impl!(SaturatingSub, saturating_sub, i32);
+saturating_impl!(SaturatingSub, saturating_sub, i64);
+saturating_impl!(SaturatingSub, saturating_sub, isize);
+saturating_impl!(SaturatingSub, saturating_sub, i128);
+
+/// Performs multiplication that saturates at the numeric bounds instead of overflowing.
+pub trait SaturatingMul: Sized + Mul<Self, Output = Self> {
+ /// Saturating multiplication. Computes `self * other`, saturating at the relevant high or low boundary of
+ /// the type.
+ fn saturating_mul(&self, v: &Self) -> Self;
+}
+
+saturating_impl!(SaturatingMul, saturating_mul, u8);
+saturating_impl!(SaturatingMul, saturating_mul, u16);
+saturating_impl!(SaturatingMul, saturating_mul, u32);
+saturating_impl!(SaturatingMul, saturating_mul, u64);
+saturating_impl!(SaturatingMul, saturating_mul, usize);
+saturating_impl!(SaturatingMul, saturating_mul, u128);
+
+saturating_impl!(SaturatingMul, saturating_mul, i8);
+saturating_impl!(SaturatingMul, saturating_mul, i16);
+saturating_impl!(SaturatingMul, saturating_mul, i32);
+saturating_impl!(SaturatingMul, saturating_mul, i64);
+saturating_impl!(SaturatingMul, saturating_mul, isize);
+saturating_impl!(SaturatingMul, saturating_mul, i128);
+
+// TODO: add SaturatingNeg for signed integer primitives once the saturating_neg() API is stable.
+
+#[test]
+fn test_saturating_traits() {
+ fn saturating_add<T: SaturatingAdd>(a: T, b: T) -> T {
+ a.saturating_add(&b)
+ }
+ fn saturating_sub<T: SaturatingSub>(a: T, b: T) -> T {
+ a.saturating_sub(&b)
+ }
+ fn saturating_mul<T: SaturatingMul>(a: T, b: T) -> T {
+ a.saturating_mul(&b)
+ }
+ assert_eq!(saturating_add(255, 1), 255u8);
+ assert_eq!(saturating_add(127, 1), 127i8);
+ assert_eq!(saturating_add(-128, -1), -128i8);
+ assert_eq!(saturating_sub(0, 1), 0u8);
+ assert_eq!(saturating_sub(-128, 1), -128i8);
+ assert_eq!(saturating_sub(127, -1), 127i8);
+ assert_eq!(saturating_mul(255, 2), 255u8);
+ assert_eq!(saturating_mul(127, 2), 127i8);
+ assert_eq!(saturating_mul(-128, 2), -128i8);
+}