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//! Right shift via the [`Shr`] trait.
use super::U384;
use core::ops::Shr;
/// Shifts the value right by `n` bits, zero-filling the high bits.
///
/// Delegates to [`U384::shr_bits`]. For shifts of 384 or more, the
/// result is zero.
///
/// # Examples
///
/// ```
/// use cnfy_uint::u384::U384;
///
/// let a = U384::from_be_limbs([0, 0, 0, 0, 0, 8]);
/// assert_eq!(a >> 3, U384::from_be_limbs([0, 0, 0, 0, 0, 1]));
/// ```
impl Shr<u32> for U384 {
type Output = U384;
#[inline]
fn shr(self, rhs: u32) -> U384 {
self.shr_bits(rhs)
}
}
#[cfg(test)]
mod ai_tests {
use super::*;
/// Shift by zero is identity.
#[test]
fn identity() {
let a = U384::from_be_limbs([0x1234, 0x5678, 0x9ABC, 0xDEF0, 0x1111, 0x2222]);
assert_eq!(a >> 0, a);
}
/// Shift by 1 halves the value.
#[test]
fn shift_one() {
assert_eq!(
U384::from_be_limbs([0, 0, 0, 0, 0, 8]) >> 1,
U384::from_be_limbs([0, 0, 0, 0, 0, 4]),
);
}
/// Shift by 64 moves one limb.
#[test]
fn one_limb() {
let a = U384::from_be_limbs([0, 0, 0, 0, 1, 0]);
assert_eq!(a >> 64, U384::from_be_limbs([0, 0, 0, 0, 0, 1]));
}
/// Shift by 384 or more produces zero.
#[test]
fn full_shift() {
assert_eq!(U384::MAX >> 384, U384::ZERO);
assert_eq!(U384::MAX >> 500, U384::ZERO);
}
/// Matches shr_bits behavior.
#[test]
fn matches_shr_bits() {
let a = U384::from_be_limbs([0, 0, 0x1234, 0x5678, 0x9ABC, 0xDEF0]);
assert_eq!(a >> 17, a.shr_bits(17));
}
}