Use ff crate for Field traits

Cargo.toml

@@ -11,12 +11,16 @@ version = "0.1.0"
 [dependencies]
 rand = "0.4"
 bit-vec = "0.4.4"
+ff = "0.4"
 futures = "0.1"
 futures-cpupool = "0.1"
 num_cpus = "1"
 crossbeam = "0.3"
-pairing = "0.14"
 byteorder = "1"
 
+[dependencies.pairing]
+git = "https://github.com/ebfull/pairing"
+rev = "183a64b08e9dc7067f78624ec161371f1829623e"
+
 [features]
 default = []

src/domain.rs

@@ -10,10 +10,9 @@
 //! This allows us to perform polynomial operations in O(n)
 //! by performing an O(n log n) FFT over such a domain.
 
+use ff::{Field, PrimeField};
 use pairing::{
     Engine,
-    Field,
-    PrimeField,
     CurveProjective
 };
 

src/groth16/generator.rs

@@ -2,10 +2,9 @@ use rand::Rng;
 
 use std::sync::Arc;
 
+use ff::{Field, PrimeField};
 use pairing::{
     Engine,
-    PrimeField,
-    Field,
     Wnaf,
     CurveProjective,
     CurveAffine

src/groth16/mod.rs

@@ -486,8 +486,8 @@ mod test_with_bls12_381 {
     use super::*;
     use {Circuit, SynthesisError, ConstraintSystem};
 
+    use ff::Field;
     use rand::{Rand, thread_rng};
-    use pairing::{Field};
     use pairing::bls12_381::{Bls12, Fr};
 
     #[test]

src/groth16/prover.rs

@@ -4,10 +4,9 @@ use std::sync::Arc;
 
 use futures::Future;
 
+use ff::{Field, PrimeField};
 use pairing::{
     Engine,
-    PrimeField,
-    Field,
     CurveProjective,
     CurveAffine
 };

src/groth16/tests/dummy_engine.rs

@@ -1,13 +1,10 @@
+use ff::{
+    Field, LegendreSymbol, PrimeField, PrimeFieldDecodingError,
+    PrimeFieldRepr, ScalarEngine, SqrtField};
 use pairing::{
     Engine,
-    PrimeField,
-    PrimeFieldRepr,
-    Field,
-    SqrtField,
-    LegendreSymbol,
     CurveProjective,
     CurveAffine,
-    PrimeFieldDecodingError,
     GroupDecodingError,
     EncodedPoint
 };
@@ -263,8 +260,11 @@ impl PrimeField for Fr {
 #[derive(Clone)]
 pub struct DummyEngine;
 
-impl Engine for DummyEngine {
+impl ScalarEngine for DummyEngine {
     type Fr = Fr;
+}
+
+impl Engine for DummyEngine {
     type G1 = Fr;
     type G1Affine = Fr;
     type G2 = Fr;

src/groth16/tests/mod.rs

@@ -1,8 +1,5 @@
-use pairing::{
-    Engine,
-    Field,
-    PrimeField
-};
+use ff::{Field, PrimeField};
+use pairing::Engine;
 
 mod dummy_engine;
 use self::dummy_engine::*;

src/groth16/verifier.rs

@@ -1,8 +1,8 @@
+use ff::PrimeField;
 use pairing::{
     Engine,
     CurveProjective,
     CurveAffine,
-    PrimeField
 };
 
 use super::{

src/lib.rs

@@ -1,3 +1,4 @@
+extern crate ff;
 extern crate pairing;
 extern crate rand;
 extern crate num_cpus;
@@ -12,7 +13,8 @@ mod multiexp;
 pub mod domain;
 pub mod groth16;
 
-use pairing::{Engine, Field};
+use ff::Field;
+use pairing::Engine;
 
 use std::ops::{Add, Sub};
 use std::fmt;

src/multiexp.rs

@@ -1,10 +1,7 @@
+use ff::{Field, PrimeField, PrimeFieldRepr, ScalarEngine};
 use pairing::{
     CurveAffine,
     CurveProjective,
-    Engine,
-    PrimeField,
-    Field,
-    PrimeFieldRepr
 };
 use std::sync::Arc;
 use std::io;
@@ -141,7 +138,7 @@ fn multiexp_inner<Q, D, G, S>(
     pool: &Worker,
     bases: S,
     density_map: D,
-    exponents: Arc<Vec<<<G::Engine as Engine>::Fr as PrimeField>::Repr>>,
+    exponents: Arc<Vec<<<G::Engine as ScalarEngine>::Fr as PrimeField>::Repr>>,
     mut skip: u32,
     c: u32,
     handle_trivial: bool
@@ -167,8 +164,8 @@ fn multiexp_inner<Q, D, G, S>(
             // Create space for the buckets
             let mut buckets = vec![<G as CurveAffine>::Projective::zero(); (1 << c) - 1];
 
-            let zero = <G::Engine as Engine>::Fr::zero().into_repr();
-            let one = <G::Engine as Engine>::Fr::one().into_repr();
+            let zero = <G::Engine as ScalarEngine>::Fr::zero().into_repr();
+            let one = <G::Engine as ScalarEngine>::Fr::one().into_repr();
 
             // Sort the bases into buckets
             for (&exp, density) in exponents.iter().zip(density_map.as_ref().iter()) {
@@ -211,7 +208,7 @@ fn multiexp_inner<Q, D, G, S>(
 
     skip += c;
 
-    if skip >= <G::Engine as Engine>::Fr::NUM_BITS {
+    if skip >= <G::Engine as ScalarEngine>::Fr::NUM_BITS {
         // There isn't another region.
         Box::new(this)
     } else {
@@ -238,7 +235,7 @@ pub fn multiexp<Q, D, G, S>(
     pool: &Worker,
     bases: S,
     density_map: D,
-    exponents: Arc<Vec<<<G::Engine as Engine>::Fr as PrimeField>::Repr>>
+    exponents: Arc<Vec<<<G::Engine as ScalarEngine>::Fr as PrimeField>::Repr>>
 ) -> Box<Future<Item=<G as CurveAffine>::Projective, Error=SynthesisError>>
     where for<'a> &'a Q: QueryDensity,
           D: Send + Sync + 'static + Clone + AsRef<Q>,
@@ -280,12 +277,12 @@ fn test_with_bls12() {
     }
 
     use rand::{self, Rand};
-    use pairing::bls12_381::Bls12;
+    use pairing::{bls12_381::Bls12, Engine};
 
     const SAMPLES: usize = 1 << 14;
 
     let rng = &mut rand::thread_rng();
-    let v = Arc::new((0..SAMPLES).map(|_| <Bls12 as Engine>::Fr::rand(rng).into_repr()).collect::<Vec<_>>());
+    let v = Arc::new((0..SAMPLES).map(|_| <Bls12 as ScalarEngine>::Fr::rand(rng).into_repr()).collect::<Vec<_>>());
     let g = Arc::new((0..SAMPLES).map(|_| <Bls12 as Engine>::G1::rand(rng).into_affine()).collect::<Vec<_>>());
 
     let naive = naive_multiexp(g.clone(), v.clone());

tests/mimc.rs

@@ -1,4 +1,5 @@
 extern crate bellman;
+extern crate ff;
 extern crate pairing;
 extern crate rand;
 
@@ -9,10 +10,8 @@ use rand::{thread_rng, Rng};
 use std::time::{Duration, Instant};
 
 // Bring in some tools for using pairing-friendly curves
-use pairing::{
-    Engine,
-    Field
-};
+use ff::Field;
+use pairing::Engine;
 
 // We're going to use the BLS12-381 pairing-friendly elliptic curve.
 use pairing::bls12_381::{