Migrate sapling-crypto to rand_core 0.4

sapling-crypto/src/jubjub/edwards.rs

@@ -8,9 +8,7 @@ use super::{
     montgomery
 };
 
-use rand::{
-    Rng
-};
+use rand_core::RngCore;
 
 use std::marker::PhantomData;
 
@@ -185,12 +183,13 @@ impl<E: JubjubEngine> Point<E, Unknown> {
         convert_subgroup(&tmp)
     }
 
-    pub fn rand<R: Rng>(rng: &mut R, params: &E::Params) -> Self
+    pub fn rand<R: RngCore>(rng: &mut R, params: &E::Params) -> Self
     {
         loop {
             let y = E::Fr::random(rng);
+            let sign = rng.next_u32() % 2 != 0;
 
-            if let Some(p) = Self::get_for_y(y, rng.gen(), params) {
+            if let Some(p) = Self::get_for_y(y, sign, params) {
                 return p;
             }
         }

sapling-crypto/src/jubjub/fs.rs

@@ -4,7 +4,7 @@ use ff::{
     LegendreSymbol::{self, *},
     PrimeField, PrimeFieldDecodingError, PrimeFieldRepr, SqrtField,
 };
-use rand::RngCore;
+use rand_core::RngCore;
 
 use super::ToUniform;
 
@@ -620,7 +620,9 @@ fn test_neg_one() {
 }
 
 #[cfg(test)]
-use rand::{SeedableRng, XorShiftRng};
+use rand_core::SeedableRng;
+#[cfg(test)]
+use rand_xorshift::XorShiftRng;
 
 #[test]
 fn test_fs_repr_ordering() {

sapling-crypto/src/jubjub/montgomery.rs

@@ -8,9 +8,7 @@ use super::{
     edwards
 };
 
-use rand::{
-    Rng
-};
+use rand_core::RngCore;
 
 use std::marker::PhantomData;
 
@@ -101,12 +99,13 @@ impl<E: JubjubEngine> Point<E, Unknown> {
         convert_subgroup(&tmp)
     }
 
-    pub fn rand<R: Rng>(rng: &mut R, params: &E::Params) -> Self
+    pub fn rand<R: RngCore>(rng: &mut R, params: &E::Params) -> Self
     {
         loop {
             let x = E::Fr::random(rng);
+            let sign = rng.next_u32() % 2 != 0;
 
-            match Self::get_for_x(x, rng.gen(), params) {
+            match Self::get_for_x(x, sign, params) {
                 Some(p) => {
                     return p
                 },

sapling-crypto/src/jubjub/tests.rs

@@ -14,7 +14,8 @@ use ff::{
     LegendreSymbol
 };
 
-use rand::{RngCore, XorShiftRng, SeedableRng};
+use rand_core::{RngCore, SeedableRng};
+use rand_xorshift::XorShiftRng;
 
 pub fn test_suite<E: JubjubEngine>(params: &E::Params) {
     test_back_and_forth::<E>(params);