fix(primitives): don't double-hex signature bytes in Signature#to_hex_bytes (#6313)

crates/primitives/src/transaction/signature.rs

@@ -181,7 +181,7 @@ impl Signature {
 
     /// Turn this signature into its hex-encoded representation.
     pub fn to_hex_bytes(&self) -> Bytes {
-        crate::hex::encode(self.to_bytes()).into()
+        self.to_bytes().into()
     }
 
     /// Calculates a heuristic for the in-memory size of the [Signature].
@@ -194,7 +194,7 @@ impl Signature {
 #[cfg(test)]
 mod tests {
     use crate::{transaction::signature::SECP256K1N_HALF, Address, Signature, B256, U256};
-    use alloy_primitives::hex;
+    use alloy_primitives::{hex, hex::FromHex, Bytes};
     use bytes::BytesMut;
     use std::str::FromStr;
 
@@ -315,6 +315,24 @@ mod tests {
         assert!(signature.size() >= 65);
     }
 
+    #[test]
+    fn test_to_hex_bytes() {
+        let signature = Signature {
+            r: U256::from_str(
+                "18515461264373351373200002665853028612451056578545711640558177340181847433846",
+            )
+            .unwrap(),
+            s: U256::from_str(
+                "46948507304638947509940763649030358759909902576025900602547168820602576006531",
+            )
+            .unwrap(),
+            odd_y_parity: false,
+        };
+
+        let expected = Bytes::from_hex("0x28ef61340bd939bc2195fe537567866003e1a15d3c71ff63e1590620aa63627667cbe9d8997f761aecb703304b3800ccf555c9f3dc64214b297fb1966a3b6d831b").unwrap();
+        assert_eq!(signature.to_hex_bytes(), expected);
+    }
+
     #[test]
     fn eip_2_reject_high_s_value() {
         // This pre-homestead transaction has a high `s` value and should be rejected by the