Add clippy (#191)

* Organize imports

Use rustfmt to organize imports.  Resolve #162

* remove unused imports

* Fix clippy complaints

* add clippy github action

* remove comment for @arnaucube

src/backends/plonky2/primitives/merkletree.rs

@@ -7,10 +7,7 @@ use plonky2::field::types::Field;
 use serde::{Deserialize, Serialize};
 
 pub use super::merkletree_circuit::*;
-use crate::backends::{
-    counter,
-    plonky2::basetypes::{hash_fields, Hash, Value, EMPTY_HASH, F},
-};
+use crate::backends::plonky2::basetypes::{hash_fields, Hash, Value, EMPTY_HASH, F};
 
 /// Implements the MerkleTree specified at
 /// https://0xparc.github.io/pod2/merkletree.html
@@ -30,7 +27,7 @@ impl MerkleTree {
             .collect::<Result<_>>()?;
 
         // Start with a leaf or conclude with an empty node as root.
-        let mut root = leaves.pop().map(|l| Node::Leaf(l)).unwrap_or(Node::None);
+        let mut root = leaves.pop().map(Node::Leaf).unwrap_or(Node::None);
 
         // Iterate over remaining leaves (if any) and add them.
         for leaf in leaves.into_iter() {
@@ -81,8 +78,6 @@ impl MerkleTree {
     /// the tree. It returns the `value` of the leaf at the given `key`, and the
     /// `MerkleProof`.
     pub fn prove(&self, key: &Value) -> Result<(Value, MerkleProof)> {
-        counter::count_tree_proof_gen();
-
         let path = keypath(self.max_depth, *key)?;
 
         let mut siblings: Vec<Hash> = Vec::new();
@@ -108,8 +103,6 @@ impl MerkleTree {
     /// the key-value pair in the leaf reached as a result of
     /// resolving `key` as well as a `MerkleProof`.
     pub fn prove_nonexistence(&self, key: &Value) -> Result<MerkleProof> {
-        counter::count_tree_proof_gen();
-
         let path = keypath(self.max_depth, *key)?;
 
         let mut siblings: Vec<Hash> = Vec::new();
@@ -373,8 +366,6 @@ impl Node {
 
     // adds the leaf at the tree from the current node (self), without computing any hash
     pub(crate) fn add_leaf(&mut self, lvl: usize, max_depth: usize, leaf: Leaf) -> Result<()> {
-        counter::count_tree_insert();
-
         if lvl >= max_depth {
             return Err(anyhow!("max depth reached"));
         }
@@ -610,11 +601,8 @@ pub mod tests {
         let (v, proof) = tree.prove(&Value::from(13))?;
         assert_eq!(v, Value::from(1013));
         println!("{}", proof);
-        println!("after proof generation, {}", counter::counter_get());
 
-        counter::counter_reset();
         MerkleTree::verify(32, tree.root(), &proof, &key, &value)?;
-        println!("after verify, {}", counter::counter_get());
 
         // Exclusion checks
         let key = Value::from(12);

src/backends/plonky2/primitives/merkletree_circuit.rs

@@ -2,7 +2,7 @@
 //! offers two different circuits:
 //!
 //! - `MerkleProofCircuit`: allows to verify both proofs of existence and proofs
-//! non-existence with the same circuit.
+//!   non-existence with the same circuit.
 //! - `MerkleProofExistenceCircuit`: allows to verify proofs of existence only.
 //!
 //! If only proofs of existence are needed, use `MerkleProofExistenceCircuit`,
@@ -154,6 +154,7 @@ impl MerkleProofGadget {
 
 impl MerkleClaimAndProofTarget {
     /// assigns the given values to the targets
+    #[allow(clippy::too_many_arguments)]
     pub fn set_targets(
         &self,
         pw: &mut PartialWitness<F>,
@@ -293,9 +294,9 @@ impl MerkleProofExistenceTarget {
 fn compute_root_from_leaf(
     max_depth: usize,
     builder: &mut CircuitBuilder<F, D>,
-    path: &Vec<BoolTarget>,
+    path: &[BoolTarget],
     leaf_hash: &HashOutTarget,
-    siblings: &Vec<HashOutTarget>,
+    siblings: &[HashOutTarget],
 ) -> Result<HashOutTarget> {
     assert_eq!(siblings.len(), max_depth);
     // Convenience constants
@@ -322,7 +323,7 @@ fn compute_root_from_leaf(
         .rev()
         .collect::<Vec<_>>();
 
-    let mut h = leaf_hash.clone();
+    let mut h = *leaf_hash;
     for (i, (sibling, selector)) in std::iter::zip(siblings, &sibling_selectors)
         .enumerate()
         .rev()

src/backends/plonky2/primitives/signature.rs

@@ -55,7 +55,7 @@ pub struct Signature(pub(crate) Proof);
 
 /// Implements the key generation and the computation of proof-based signatures.
 impl SecretKey {
-    pub fn new() -> Self {
+    pub fn new_rand() -> Self {
         // note: the `F::rand()` internally uses `rand::rngs::OsRng`
         Self(Value(std::array::from_fn(|_| F::rand())))
     }
@@ -189,9 +189,9 @@ impl SignatureInternalCircuit {
         msg: Value,
         s: Value,
     ) -> Result<()> {
-        pw.set_target_arr(&self.sk_targ, &sk.0 .0.to_vec())?;
+        pw.set_target_arr(&self.sk_targ, sk.0 .0.as_ref())?;
         pw.set_hash_target(self.pk_targ, HashOut::<F>::from_vec(pk.0 .0.to_vec()))?;
-        pw.set_target_arr(&self.msg_targ, &msg.0.to_vec())?;
+        pw.set_target_arr(&self.msg_targ, msg.0.as_ref())?;
         pw.set_hash_target(self.s_targ, HashOut::<F>::from_vec(s.0.to_vec()))?;
 
         Ok(())
@@ -205,7 +205,7 @@ pub mod tests {
 
     #[test]
     fn test_signature() -> Result<()> {
-        let sk = SecretKey::new();
+        let sk = SecretKey::new_rand();
         let pk = sk.public_key();
 
         let msg = Value::from(42);

src/backends/plonky2/primitives/signature_circuit.rs

@@ -175,7 +175,7 @@ pub mod tests {
     #[test]
     fn test_signature_gadget() -> Result<()> {
         // generate a valid signature
-        let sk = SecretKey::new();
+        let sk = SecretKey::new_rand();
         let pk = sk.public_key();
         let msg = Value::from(42);
         let sig = sk.sign(msg)?;
@@ -206,7 +206,7 @@ pub mod tests {
     #[test]
     fn test_signature_gadget_disabled() -> Result<()> {
         // generate a valid signature
-        let sk = SecretKey::new();
+        let sk = SecretKey::new_rand();
         let pk = sk.public_key();
         let msg = Value::from(42);
         let sig = sk.sign(msg)?;