chore: update to ff/group 0.13 (#166)

* chore: update to ff/group 0.13 and associated dependencies

Updates:
- zkcrypto/ff, zkcrypto/group to 0.13,
- bellperson to 0.25,
- pasta_curves to 0.5.1, and removes the fil_pasta_curves fork
- pasta-msm should no longer need a fork (WIP)

Adapts source in function, mostly for const usage and API updates.

* expose the portable feature of pasta-MSM

* update pointer to pasta-msm

* Clippy

---------

Co-authored-by: François Garillot <francois@garillot.net>

src/bellperson/mod.rs

@@ -20,7 +20,7 @@ mod tests {
     cs: &mut CS,
   ) -> Result<(), SynthesisError> {
     // get two bits as input and check that they are indeed bits
-    let a = AllocatedNum::alloc(cs.namespace(|| "a"), || Ok(Fr::one()))?;
+    let a = AllocatedNum::alloc(cs.namespace(|| "a"), || Ok(Fr::ONE))?;
     let _ = a.inputize(cs.namespace(|| "a is input"));
     cs.enforce(
       || "check a is 0 or 1",
@@ -28,7 +28,7 @@ mod tests {
       |lc| lc + a.get_variable(),
       |lc| lc,
     );
-    let b = AllocatedNum::alloc(cs.namespace(|| "b"), || Ok(Fr::one()))?;
+    let b = AllocatedNum::alloc(cs.namespace(|| "b"), || Ok(Fr::ONE))?;
     let _ = b.inputize(cs.namespace(|| "b is input"));
     cs.enforce(
       || "check b is 0 or 1",

src/bellperson/r1cs.rs

@@ -102,7 +102,7 @@ fn add_constraint<S: PrimeField>(
 ) {
   let (A, B, C, nn) = X;
   let n = **nn;
-  let one = S::one();
+  let one = S::ONE;
 
   let add_constraint_component = |index: Index, coeff, V: &mut Vec<_>| {
     match index {

src/bellperson/shape_cs.rs

@@ -73,7 +73,7 @@ fn proc_lc<Scalar: PrimeField>(
   for (var, &coeff) in terms.iter() {
     map
       .entry(OrderedVariable(var))
-      .or_insert_with(Scalar::zero)
+      .or_insert_with(|| Scalar::ZERO)
       .add_assign(&coeff);
   }
 
@@ -144,7 +144,7 @@ where
       writeln!(s, "INPUT {}", &input).unwrap()
     }
 
-    let negone = -<G::Scalar>::one();
+    let negone = -<G::Scalar>::ONE;
 
     let powers_of_two = (0..G::Scalar::NUM_BITS)
       .map(|i| G::Scalar::from(2u64).pow_vartime([u64::from(i)]))
@@ -161,7 +161,7 @@ where
         }
         is_first = false;
 
-        if coeff != <G::Scalar>::one() && coeff != negone {
+        if coeff != <G::Scalar>::ONE && coeff != negone {
           for (i, x) in powers_of_two.iter().enumerate() {
             if x == &coeff {
               write!(s, "2^{i} . ").unwrap();

src/bellperson/solver.rs

@@ -91,7 +91,7 @@ where
   type Root = Self;
 
   fn new() -> Self {
-    let input_assignment = vec![G::Scalar::one()];
+    let input_assignment = vec![G::Scalar::ONE];
     let mut d = DensityTracker::new();
     d.add_element();