rm 128 bit constant

src/constants.rs

@@ -1,5 +1,3 @@
-// used for challenge r, so when computing r^2 it does not overflow the field
-pub const N_BITS_CHALLENGE: usize = 128;
 // used for committed instances hash, so when going to the other curve of the cycle it does not
 // overflow the scalar field
 pub const N_BITS_HASH: usize = 250;

src/folding/nova/circuits.rs

@@ -436,7 +436,6 @@ pub mod tests {
     use tracing_subscriber::layer::SubscriberExt;
 
     use crate::ccs::r1cs::tests::{get_test_r1cs, get_test_z};
-    use crate::constants::N_BITS_CHALLENGE;
     use crate::folding::nova::{nifs::NIFS, traits::NovaR1CS, Witness};
     use crate::frontend::arkworks::{extract_r1cs, extract_z};
     use crate::pedersen::Pedersen;
@@ -521,7 +520,7 @@ pub mod tests {
         // transcript
         let poseidon_config = poseidon_test_config::<Fr>();
         let mut tr = PoseidonTranscript::<Projective>::new(&poseidon_config);
-        let r_bits = tr.get_challenge_nbits(N_BITS_CHALLENGE);
+        let r_bits = tr.get_challenge_nbits(128);
         let r_Fr = Fr::from_bigint(BigInteger::from_bits_le(&r_bits)).unwrap();
 
         let (_, ci3) =

src/transcript/poseidon.rs

@@ -171,7 +171,7 @@ pub mod tests {
 
     #[test]
     fn test_transcript_and_transcriptvar_nbits() {
-        let nbits = crate::constants::N_BITS_CHALLENGE;
+        let nbits = 128;
 
         // use 'native' transcript
         let config = poseidon_test_config::<Fq>();