Add an example doctest for Scalar.invert().

This commit is contained in:
Isis Lovecruft 2018-07-05 00:15:15 +00:00
parent faf8609246
commit 03154d47ec
Failed to extract signature

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@ -535,6 +535,32 @@ impl Scalar {
/// # Returns
///
/// The multiplicative inverse of the this `Scalar`.
///
/// # Example
///
/// ```
/// use curve25519_dalek::scalar::Scalar;
///
/// // x = 2238329342913194256032495932344128051776374960164957527413114840482143558222
/// let X: Scalar = Scalar::from_bytes_mod_order([
/// 0x4e, 0x5a, 0xb4, 0x34, 0x5d, 0x47, 0x08, 0x84,
/// 0x59, 0x13, 0xb4, 0x64, 0x1b, 0xc2, 0x7d, 0x52,
/// 0x52, 0xa5, 0x85, 0x10, 0x1b, 0xcc, 0x42, 0x44,
/// 0xd4, 0x49, 0xf4, 0xa8, 0x79, 0xd9, 0xf2, 0x04,
/// ]);
/// // 1/x = 6859937278830797291664592131120606308688036382723378951768035303146619657244
/// let XINV: Scalar = Scalar::from_bytes_mod_order([
/// 0x1c, 0xdc, 0x17, 0xfc, 0xe0, 0xe9, 0xa5, 0xbb,
/// 0xd9, 0x24, 0x7e, 0x56, 0xbb, 0x01, 0x63, 0x47,
/// 0xbb, 0xba, 0x31, 0xed, 0xd5, 0xa9, 0xbb, 0x96,
/// 0xd5, 0x0b, 0xcd, 0x7a, 0x3f, 0x96, 0x2a, 0x0f,
/// ]);
///
/// let inv_X: Scalar = X.invert();
/// assert!(XINV == inv_X);
/// let should_be_one: Scalar = &inv_X * &X;
/// assert!(should_be_one == Scalar::one());
/// ```
pub fn invert(&self) -> Scalar {
self.unpack().invert().pack()
}