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//! Construction of a `U384` from a six-element `[u64; 6]` limb array.
use super::U384;
impl U384 {
/// Creates a new [`U384`] from a six-element array of `u64` limbs in
/// big-endian order: `[w0, w1, w2, w3, w4, w5]` where `w0` is the most
/// significant and `w5` is the least significant.
///
/// The input is reversed into internal little-endian storage.
///
/// # Examples
///
/// ```
/// use cnfy_uint::u384::U384;
///
/// let value = U384::from_be_limbs([0, 0, 0, 0, 0, 42]);
/// assert_eq!(value.to_be_limbs(), [0, 0, 0, 0, 0, 42]);
/// ```
#[inline]
pub const fn from_be_limbs(value: [u64; 6]) -> Self {
Self([value[5], value[4], value[3], value[2], value[1], value[0]])
}
}
#[cfg(test)]
mod ai_tests {
use super::*;
/// Constructing from six zeros yields a zero value.
#[test]
fn zero() {
let z = U384::from_be_limbs([0; 6]);
assert_eq!(z.0, [0; 6]);
}
/// All limbs are stored in reversed (LE) positions.
#[test]
fn limb_order() {
let v = U384::from_be_limbs([1, 2, 3, 4, 5, 6]);
assert_eq!(v.0[0], 6); // BE[5] -> LE[0]
assert_eq!(v.0[5], 1); // BE[0] -> LE[5]
}
/// Maximum value fills all six limbs.
#[test]
fn max_value() {
let v = U384::from_be_limbs([u64::MAX; 6]);
assert_eq!(v.0, [u64::MAX; 6]);
}
}