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Implement BitOr and BitOrAssign for the NonZero integer types #69813

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52 changes: 52 additions & 0 deletions src/libcore/num/mod.rs
Original file line number Diff line number Diff line change
Expand Up @@ -8,6 +8,7 @@ use crate::convert::Infallible;
use crate::fmt;
use crate::intrinsics;
use crate::mem;
use crate::ops::{BitOr, BitOrAssign};
use crate::str::FromStr;

// Used because the `?` operator is not allowed in a const context.
Expand Down Expand Up @@ -110,6 +111,57 @@ assert_eq!(size_of::<Option<core::num::", stringify!($Ty), ">>(), size_of::<", s
}
}

#[stable(feature = "nonzero_bitor", since = "1.43.0")]
impl BitOr for $Ty {
type Output = Self;
#[inline]
fn bitor(self, rhs: Self) -> Self::Output {
// Safety: since `self` and `rhs` are both nonzero, the
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I remember hearing that libcore was going to require safety annotations, so I added them even though they're trivial. I can remove them (or remove the duplicates) if it's extraneous or noisy.

I also used new_unchecked instead of just doing $Ty(...) (despite it being in scope) to call attention to the unsafety but similarly don't have strong opinions here.

// result of the bitwise-or will be nonzero.
unsafe { $Ty::new_unchecked(self.get() | rhs.get()) }
}
}

#[stable(feature = "nonzero_bitor", since = "1.43.0")]
impl BitOr<$Int> for $Ty {
type Output = Self;
#[inline]
fn bitor(self, rhs: $Int) -> Self::Output {
// Safety: since `self` is nonzero, the result of the
// bitwise-or will be nonzero regardless of the value of
// `rhs`.
unsafe { $Ty::new_unchecked(self.get() | rhs) }
}
}

#[stable(feature = "nonzero_bitor", since = "1.43.0")]
impl BitOr<$Ty> for $Int {
type Output = $Ty;
#[inline]
fn bitor(self, rhs: $Ty) -> Self::Output {
// Safety: since `rhs` is nonzero, the result of the
// bitwise-or will be nonzero regardless of the value of
// `self`.
unsafe { $Ty::new_unchecked(self | rhs.get()) }
}
}

#[stable(feature = "nonzero_bitor", since = "1.43.0")]
impl BitOrAssign for $Ty {
#[inline]
fn bitor_assign(&mut self, rhs: Self) {
*self = *self | rhs;
}
}

#[stable(feature = "nonzero_bitor", since = "1.43.0")]
impl BitOrAssign<$Int> for $Ty {
#[inline]
fn bitor_assign(&mut self, rhs: $Int) {
*self = *self | rhs;
}
}

impl_nonzero_fmt! {
#[$stability] (Debug, Display, Binary, Octal, LowerHex, UpperHex) for $Ty
}
Expand Down
35 changes: 35 additions & 0 deletions src/libcore/tests/nonzero.rs
Original file line number Diff line number Diff line change
Expand Up @@ -141,3 +141,38 @@ fn test_from_str() {
Some(IntErrorKind::Overflow)
);
}

#[test]
fn test_nonzero_bitor() {
let nz_alt = NonZeroU8::new(0b1010_1010).unwrap();
let nz_low = NonZeroU8::new(0b0000_1111).unwrap();

let both_nz: NonZeroU8 = nz_alt | nz_low;
assert_eq!(both_nz.get(), 0b1010_1111);

let rhs_int: NonZeroU8 = nz_low | 0b1100_0000u8;
assert_eq!(rhs_int.get(), 0b1100_1111);

let rhs_zero: NonZeroU8 = nz_alt | 0u8;
assert_eq!(rhs_zero.get(), 0b1010_1010);

let lhs_int: NonZeroU8 = 0b0110_0110u8 | nz_alt;
assert_eq!(lhs_int.get(), 0b1110_1110);

let lhs_zero: NonZeroU8 = 0u8 | nz_low;
assert_eq!(lhs_zero.get(), 0b0000_1111);
}

#[test]
fn test_nonzero_bitor_assign() {
let mut target = NonZeroU8::new(0b1010_1010).unwrap();

target |= NonZeroU8::new(0b0000_1111).unwrap();
assert_eq!(target.get(), 0b1010_1111);

target |= 0b0001_0000;
assert_eq!(target.get(), 0b1011_1111);

target |= 0;
assert_eq!(target.get(), 0b1011_1111);
}