midnight-curves 0.2.0

Implementation of BLS12 381 and Jubjub curves.
Documentation 
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pub mod curve;
pub mod engine;
pub mod field;
pub mod field_halo2curves;
pub mod pairing;

pub(crate) fn hex_to_bytes(hex: &str) -> Vec<u8> {
    hex::decode(hex).expect("Invalid hex string")
}

/// Helper function to convert a hex string to a field element.
/// This is used in the tests for BN256 curve, which uses little-endian internal
/// representation for its field elements. The input of this function should
/// have the opposite endianness, so it expects big-endian hex strings.
#[cfg(any(test, feature = "dev-curves"))]
pub(crate) fn hex_to_field<F: ff::PrimeField>(hex: &str) -> F {
    let mut bytes = hex_to_bytes(hex);
    bytes.reverse();
    let mut repr = F::Repr::default();
    repr.as_mut()[..bytes.len()].copy_from_slice(&bytes);
    F::from_repr(repr).unwrap()
}

/// Helper function to create a point from hex coordinates.
/// Assuming the field elements use little-endian internal representation, this
/// function expects coordinates as big-endian hex strings in canonical form.
#[cfg(any(test, feature = "dev-curves"))]
pub(crate) fn point_from_hex<C>(x_hex: &str, y_hex: &str) -> C
where
    C: crate::CurveAffine,
    C::Base: ff::PrimeField,
{
    let x = hex_to_field(x_hex);
    let y = hex_to_field(y_hex);
    C::from_xy(x, y).expect("Invalid point coordinates")
}