chore: change to chacha based Rng in tests

Cargo.toml

@@ -60,6 +60,7 @@ winter-math = { version = "0.8", default-features = false }
 winter-utils = { version = "0.8", default-features = false }
 
 [dev-dependencies]
+rand_chacha = { version = "0.3", default-features = false }
 criterion = { version = "0.5", features = ["html_reports"] }
 getrandom = { version = "0.2", features = ["js"] }
 hex = { version = "0.4", default-features = false, features = ["alloc"] }

src/dsa/rpo_falcon512/keys/mod.rs

@@ -15,14 +15,16 @@ pub use secret_key::SecretKey;
 
 #[cfg(test)]
 mod tests {
-    use crate::{dsa::rpo_falcon512::SecretKey, rand::RpoRandomCoin, Word, ONE, ZERO};
+    use crate::{dsa::rpo_falcon512::SecretKey, Word, ONE};
+    use rand::SeedableRng;
+    use rand_chacha::ChaCha20Rng;
     use winter_math::FieldElement;
     use winter_utils::{Deserializable, Serializable};
 
     #[test]
     fn test_falcon_verification() {
-        let seed = [ZERO; 4];
-        let mut rng = RpoRandomCoin::new(seed);
+        let seed = [0_u8; 32];
+        let mut rng = ChaCha20Rng::from_seed(seed);
 
         // generate random keys
         let sk = SecretKey::with_rng(&mut rng);

src/dsa/rpo_falcon512/signature.rs

@@ -356,12 +356,13 @@ fn are_coefficients_valid(x: &[i16]) -> bool {
 #[cfg(test)]
 mod tests {
     use super::{super::SecretKey, *};
-    use crate::{rand::RpoRandomCoin, ZERO};
+    use rand::SeedableRng;
+    use rand_chacha::ChaCha20Rng;
 
     #[test]
     fn test_serialization_round_trip() {
-        let seed = [ZERO; 4];
-        let mut rng = RpoRandomCoin::new(seed);
+        let seed = [0_u8; 32];
+        let mut rng = ChaCha20Rng::from_seed(seed);
 
         let sk = SecretKey::with_rng(&mut rng);
         let signature = sk.sign_with_rng(Word::default(), &mut rng);