serdes failed for secp256k1 curve about halo2curves

[davidnevadoc]

Thanks for pointing this out! Could you have a look at #8 and let me know if it fixes the issue? @zhenfeizhang

[zhenfeizhang]

Yes it fixed the issue.

I suggest to replace/add the following to the curve test in the fix:

pub fn curve_tests<G: CurveExt>() {
    is_on_curve::<G>();
    equality::<G>();
    projective_to_affine_affine_to_projective::<G>();
    projective_addition::<G>();
    mixed_addition::<G>();
    multiplication::<G>();
    batch_normalize::<G>();
    serdes::<G>();
}

fn serdes<G: CurveExt>() {
    for _ in 0..100 {
        let projective_point = G::random(OsRng);
        let affine_point: G::AffineExt = projective_point.into();
        let projective_repr = projective_point.to_bytes();
        let affine_repr = affine_point.to_bytes();

        let projective_point_rec = G::from_bytes(&projective_repr).unwrap();
        let projective_point_rec_unchecked = G::from_bytes(&projective_repr).unwrap();
        let affine_point_rec = G::AffineExt::from_bytes(&affine_repr).unwrap();
        let affine_point_rec_unchecked = G::AffineExt::from_bytes(&affine_repr).unwrap();

        assert_eq!(projective_point, projective_point_rec);
        assert_eq!(projective_point, projective_point_rec_unchecked);
        assert_eq!(affine_point, affine_point_rec);
        assert_eq!(affine_point, affine_point_rec_unchecked);
    }
}

[davidnevadoc]

Good idea! Added in 280141c