update: Remove wasm feature

As @arnaucube correctly suggested to me, the `wasm` feature can be omitted as the `wasmer` loader does not require it.

Therefore, feature set, CI and code has been updated accordingly.
Also, the browser feature has been renamed to `circom-browser`.

Author: CPerezz

.github/scripts/wasm-target-test-build.sh

@@ -15,7 +15,7 @@ cp "${GIT_ROOT}/rust-toolchain" .
 rustup target add wasm32-unknown-unknown wasm32-wasi 
 
 # add dependencies
-cargo add --path "${GIT_ROOT}/folding-schemes" --features wasm, parallel
+cargo add --path "${GIT_ROOT}/folding-schemes" --features circom-browser
 cargo add getrandom --features js --target wasm32-unknown-unknown
 
 # test build for wasm32-* targets

.github/workflows/ci.yml

@@ -43,7 +43,7 @@ jobs:
         feature_set: [basic]
         include:
           - feature_set: basic
-            features: --features default,light-test
+            features: --features default, light-test
     steps:
       - uses: actions/checkout@v2
       - uses: actions-rs/toolchain@v1
@@ -99,7 +99,7 @@ jobs:
         uses: actions-rs/cargo@v1
         with:
           command: build
-          args: -p folding-schemes --no-default-features --target ${{ matrix.target }} --features "wasm, parallel"
+          args: -p folding-schemes --target ${{ matrix.target }} --features circom-frontend
       - name: Run wasm-compat script
         run: |
           chmod +x .github/scripts/wasm-target-test-build.sh
@@ -156,13 +156,13 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        feature_set: [basic, wasm]
+        feature_set: [basic, circom-browser]
         include:
           - feature_set: basic
             features: --features default,light-test
-            # We only want to test `folding-schemes` package with `wasm` feature.
-          - feature_set: wasm
-            features: -p folding-schemes --features wasm,parallel --target wasm32-unknown-unknown
+            # We only want to test `folding-schemes` package with `circom-browser` feature.
+          - feature_set: circom-browser
+            features: -p folding-schemes --features circom-browser, parallel --target wasm32-unknown-unknown
     steps:
       - uses: actions/checkout@v2
       - uses: actions-rs/toolchain@v1

folding-schemes/Cargo.toml

@@ -81,8 +81,7 @@ getrandom = { version = "0.2", features = ["js"] }
 [features]
 default = ["ark-circom/default", "parallel"]
 parallel = []
-wasm = ["ark-circom/wasm"]
-browser = ["wasm", "byteorder"]
+circom-browser = ["ark-circom/wasm", "byteorder"]
 light-test = []
 
 

folding-schemes/src/folding/nova/circuits.rs

@@ -411,7 +411,7 @@ where
         // get z_{i+1} from the F circuit
         let i_usize = self.i_usize.unwrap_or(0);
 
-        // If we are in the browser-frontend case. The witness is already loaded within
+        // If we are in the circom-browser-frontend case. The witness is already loaded within
         // self.F.witness. This was done at `self.prove_step()` fn.
         let z_i1 = self
             .F

folding-schemes/src/folding/nova/mod.rs

@@ -642,12 +642,12 @@ where
     fn prove_step(
         &mut self,
         mut rng: impl RngCore,
-        // This contains the full witness when we're in the browser-frontend case
+        // This contains the full witness when we're in the circom-browser-frontend case
         external_inputs: Vec<C1::ScalarField>,
         // Nova does not support multi-instances folding
         _other_instances: Option<Self::MultiCommittedInstanceWithWitness>,
     ) -> Result<(), Error> {
-        #[cfg(feature = "browser")]
+        #[cfg(feature = "circom-browser")]
         {
             // Slice and separate between external inputs and frontend witness.
             let (frontend_witness, external_inputs) =
@@ -664,7 +664,7 @@ where
                     (None, external_inputs)
                 };
 
-            // If we are in the browser-case (frontend_witness = Some(witness)) then we load the witness into the FCircuit.
+            // If we are in the circom-browser-case (frontend_witness = Some(witness)) then we load the witness into the FCircuit.
             if let Some(witness) = frontend_witness {
                 self.F.load_witness(witness)
             };

folding-schemes/src/frontend/circom/mod.rs

@@ -13,11 +13,11 @@ use num_bigint::BigInt;
 use std::rc::Rc;
 use std::{fmt, usize};
 
-#[cfg(feature = "browser")]
+#[cfg(feature = "circom-browser")]
 pub mod browser;
 pub mod utils;
 
-#[cfg(feature = "browser")]
+#[cfg(feature = "circom-browser")]
 pub use browser::{load_witness_from_bin_reader, CircomFCircuitBrowser};
 use utils::CircomWrapper;
 
@@ -38,7 +38,7 @@ impl<F: PrimeField> fmt::Debug for CustomStepNative<F> {
     }
 }
 
-/// This circuit is the one we will use in order to fold circom circuits
+/// This circuit is the one we will use in order to fold Circom circuits
 /// from a non-browser environment.
 #[derive(Clone, Debug)]
 pub struct CircomFCircuit<F: PrimeField> {

folding-schemes/src/frontend/mod.rs

@@ -50,10 +50,10 @@ pub trait FCircuit<F: PrimeField>: Clone + Debug {
     ) -> Result<Vec<FpVar<F>>, SynthesisError>;
 
     /// Allows to load pre-generated witness into the FCircuit implementor.
-    /// This is only needed by the browser use cases where we have already computed our
+    /// This is only needed by the circom-browser use cases where we have already computed our
     /// witness there. And we need a way to load it into the FCircuit since it's already computed.
     ///
-    /// By default this method will simply do nothing. Only in the browser FCircuit implementors this will have usage.
+    /// By default this method will simply do nothing. Only in the circom-browser FCircuit implementors this will have usage.
     fn load_witness(&mut self, _witness: Vec<F>) {}
 }