chore: fix clippy

benches/compressed-snark.rs

@@ -217,7 +217,7 @@ impl<F: PrimeField> StepCircuit<F> for NonTrivialCircuit<F> {
     let mut y = x.clone();
     for i in 0..self.num_cons {
       y = x.square(cs.namespace(|| format!("x_sq_{i}")))?;
-      x = y.clone();
+      x.clone_from(&y);
     }
     Ok(vec![y])
   }

benches/compute-digest.rs

@@ -68,7 +68,7 @@ impl<F: PrimeField> StepCircuit<F> for NonTrivialCircuit<F> {
     let mut y = x.clone();
     for i in 0..self.num_cons {
       y = x.square(cs.namespace(|| format!("x_sq_{i}")))?;
-      x = y.clone();
+      x.clone_from(&y);
     }
     Ok(vec![y])
   }

benches/ppsnark.rs

@@ -125,7 +125,7 @@ impl<F: PrimeField> StepCircuit<F> for NonTrivialCircuit<F> {
     let mut y = z[0].clone();
     for i in 0..self.num_cons {
       y = x.square(cs.namespace(|| format!("x_sq_{i}")))?;
-      x = y.clone();
+      x.clone_from(&y);
     }
     Ok(vec![y])
   }

benches/recursive-snark.rs

@@ -165,7 +165,7 @@ impl<F: PrimeField> StepCircuit<F> for NonTrivialCircuit<F> {
     let mut y = x.clone();
     for i in 0..self.num_cons {
       y = x.square(cs.namespace(|| format!("x_sq_{i}")))?;
-      x = y.clone();
+      x.clone_from(&y);
     }
     Ok(vec![y])
   }

src/gadgets/nonnative/mod.rs

@@ -6,16 +6,12 @@ use ff::PrimeField;
 
 trait OptionExt<T> {
   fn grab(&self) -> Result<&T, SynthesisError>;
-  fn grab_mut(&mut self) -> Result<&mut T, SynthesisError>;
 }
 
 impl<T> OptionExt<T> for Option<T> {
   fn grab(&self) -> Result<&T, SynthesisError> {
     self.as_ref().ok_or(SynthesisError::AssignmentMissing)
   }
-  fn grab_mut(&mut self) -> Result<&mut T, SynthesisError> {
-    self.as_mut().ok_or(SynthesisError::AssignmentMissing)
-  }
 }
 
 trait BitAccess {

src/gadgets/nonnative/util.rs

@@ -14,8 +14,6 @@ use std::io::{self, Write};
 pub struct Bit<Scalar: PrimeField> {
   /// The linear combination which constrain the value of the bit
   pub bit: LinearCombination<Scalar>,
-  /// The value of the bit (filled at witness-time)
-  pub value: Option<bool>,
 }
 
 #[derive(Clone)]
@@ -58,7 +56,6 @@ impl<Scalar: PrimeField> Bit<Scalar> {
 
     Ok(Self {
       bit: LinearCombination::zero() + var,
-      value,
     })
   }
 }

src/provider/bn256_grumpkin.rs

@@ -13,7 +13,7 @@ use num_traits::Num;
 // Remove this when https://github.com/zcash/pasta_curves/issues/41 resolves
 use halo2curves::{
   bn256::{
-    pairing, G1Affine as Bn256Affine, G1Compressed as Bn256Compressed, G2Affine, G2Compressed, Gt,
+    G1Affine as Bn256Affine, G1Compressed as Bn256Compressed, G2Affine, G2Compressed,
     G1 as Bn256Point, G2,
   },
   grumpkin::{G1Affine as GrumpkinAffine, G1Compressed as GrumpkinCompressed, G1 as GrumpkinPoint},
@@ -24,8 +24,6 @@ use rayon::prelude::*;
 use sha3::Shake256;
 use std::io::Read;
 
-use super::traits::PairingGroup;
-
 /// Re-exports that give access to the standard aliases used in the code base, for bn256
 pub mod bn256 {
   pub use halo2curves::bn256::{Fq as Base, Fr as Scalar, G1Affine as Affine, G1 as Point};
@@ -54,15 +52,6 @@ impl_traits!(
   "30644e72e131a029b85045b68181585d2833e84879b9709143e1f593f0000001"
 );
 
-impl PairingGroup for Bn256Point {
-  type G2 = G2;
-  type GT = Gt;
-
-  fn pairing(p: &Self, q: &Self::G2) -> Self::GT {
-    pairing(&p.affine(), &q.affine())
-  }
-}
-
 impl Group for G2 {
   type Base = bn256::Base;
   type Scalar = bn256::Scalar;

src/provider/hyperkzg.rs

@@ -486,6 +486,7 @@ mod tests {
   }
 
   #[test]
+  #[allow(clippy::assigning_clones)]
   fn test_hyperkzg_small() {
     let n = 4;
 
@@ -543,6 +544,7 @@ mod tests {
 
     // Change the proof and expect verification to fail
     let mut bad_proof = proof.clone();
+
     bad_proof.evals[0] = bad_proof.evals[1].clone();
     let mut verifier_transcript2 = Keccak256Transcript::<NE>::new(b"TestEval");
     assert!(EvaluationEngine::<Bn256, NE>::verify(
@@ -557,6 +559,7 @@ mod tests {
   }
 
   #[test]
+  #[allow(clippy::assigning_clones)]
   fn test_hyperkzg_large() {
     // test the mlkzg prover and verifier with random instances (derived from a seed)
     for num_vars in [4, 5, 6] {

src/provider/non_hiding_zeromorph.rs

@@ -308,7 +308,7 @@ where
 
     // Compute and send proof commitment pi
     let (uvproof, _uveval): (UVKZGProof<_>, UVKZGEvaluation<_>) =
-      UVKZGPCS::<E>::open(&pp.open_pp, &f, &x).map(|(proof, eval)| (proof, eval))?;
+      UVKZGPCS::<E>::open(&pp.open_pp, &f, &x)?;
 
     let proof = ZMProof {
       pi: uvproof.proof,

src/provider/traits.rs

@@ -96,19 +96,6 @@ pub trait DlogGroup:
   fn to_coordinates(&self) -> (<Self as Group>::Base, <Self as Group>::Base, bool);
 }
 
-/// A trait that defines extensions to the DlogGroup trait, to be implemented for
-/// elliptic curve groups that are pairing friendly
-pub trait PairingGroup: DlogGroup {
-  /// A type representing the second group
-  type G2: DlogGroup<Scalar = Self::Scalar, Base = Self::Base>;
-
-  /// A type representing the target group
-  type GT: PartialEq + Eq;
-
-  /// A method to compute a pairing
-  fn pairing(p: &Self, q: &Self::G2) -> Self::GT;
-}
-
 /// This implementation behaves in ways specific to the halo2curves suite of curves in:
 // - to_coordinates,
 // - vartime_multiscalar_mul, where it does not call into accelerated implementations.

src/r1cs/mod.rs

@@ -480,7 +480,7 @@ impl<E: Engine> RelaxedR1CSInstance<E> {
     let mut r_instance = RelaxedR1CSInstance::default(ck, S);
     r_instance.comm_W = instance.comm_W;
     r_instance.u = E::Scalar::ONE;
-    r_instance.X = instance.X.clone();
+    r_instance.X.clone_from(&instance.X);
     r_instance
   }
 

src/spartan/direct.rs

@@ -278,7 +278,7 @@ mod tests {
       assert!(res.is_ok());
 
       // set input to the next step
-      z_i = z_i_plus_one.clone();
+      z_i.clone_from(&z_i_plus_one);
     }
 
     // sanity: check the claimed output with a direct computation of the same

src/spartan/math.rs

@@ -1,23 +1,8 @@
 pub trait Math {
-  fn pow2(self) -> usize;
-  fn get_bits(self, num_bits: usize) -> Vec<bool>;
   fn log_2(self) -> usize;
 }
 
 impl Math for usize {
-  #[inline]
-  fn pow2(self) -> usize {
-    let base: usize = 2;
-    base.pow(self as u32)
-  }
-
-  /// Returns the `num_bits` from n in a canonical order
-  fn get_bits(self, num_bits: usize) -> Vec<bool> {
-    (0..num_bits)
-      .map(|shift_amount| ((self & (1 << (num_bits - shift_amount - 1))) > 0))
-      .collect::<Vec<bool>>()
-  }
-
   fn log_2(self) -> usize {
     assert_ne!(self, 0);
 

src/spartan/polys/mod.rs

@@ -2,9 +2,9 @@
 pub(crate) mod eq;
 pub(crate) mod identity;
 pub(crate) mod masked_eq;
-#[cfg(features = "bench")]
+#[cfg(feature = "bench")]
 pub(crate) mod multilinear;
-#[cfg(not(features = "bench"))]
+#[cfg(not(feature = "bench"))]
 pub mod multilinear;
 pub(crate) mod power;
 pub(crate) mod univariate;

src/spartan/polys/multilinear.rs

@@ -33,6 +33,7 @@ pub struct MultilinearPolynomial<Scalar: PrimeField> {
   pub(crate) Z: Vec<Scalar>, // evaluations of the polynomial in all the 2^num_vars Boolean inputs
 }
 
+#[allow(clippy::len_without_is_empty)]
 impl<Scalar: PrimeField> MultilinearPolynomial<Scalar> {
   /// Creates a new `MultilinearPolynomial` from the given evaluations.
   ///