No side-effects in getters

benches/sign.rs

@@ -157,14 +157,16 @@ fn criterion_benchmark(c: &mut Criterion) {
     let mut aggregator = SignatureAggregator::new(params, group_key, &message[..]);
 
     for i in 1..THRESHOLD_OF_PARTICIPANTS + 1 {
-        aggregator.include_signer(
-            i,
-            participants_public_comshares[(i - 1) as usize].commitments[0],
-            &participants_secret_keys[(i - 1) as usize].to_public(),
-        );
+        aggregator
+            .include_signer(
+                i,
+                participants_public_comshares[(i - 1) as usize].commitments[0],
+                &participants_secret_keys[(i - 1) as usize].to_public(),
+            )
+            .unwrap();
     }
 
-    let signers = aggregator.get_signers().clone();
+    let signers = aggregator.signers().to_vec();
     let message_hash = Secp256k1Sha256::h4(&message[..]);
     let message_hash_copy = message_hash;
 

src/error.rs

@@ -27,6 +27,8 @@ pub enum Error<C: CipherSuite> {
     ComplaintVerificationError,
     /// The index of a participant is zero
     IndexIsZero,
+    /// The index of a signer does not match the index in the public key
+    IndexMismatch(u32, u32),
     /// GroupVerifyingKey generation failure
     InvalidGroupKey,
     /// Invalid NiZK proof of knowledge
@@ -87,7 +89,14 @@ impl<C: CipherSuite> core::fmt::Display for Error<C> {
                 write!(f, "The complaint is not correct.")
             }
             Error::IndexIsZero => {
-                write!(f, "The indexs of a participant cannot be 0.")
+                write!(f, "The index of a participant cannot be 0.")
+            }
+            Error::IndexMismatch(participant_idx, pubkey_idx) => {
+                write!(
+                    f,
+                    "Index mismatch between participant index ({}) and the publick key index ({}).",
+                    participant_idx, pubkey_idx
+                )
             }
             Error::InvalidGroupKey => {
                 write!(

src/lib.rs

@@ -1455,7 +1455,7 @@
 //! #
 //! # aggregator.include_signer(1, alice_public_comshares.commitments[0], &alice_public_key);
 //! # aggregator.include_signer(3, carol_public_comshares.commitments[0], &carol_public_key);
-//! let signers = aggregator.get_signers();
+//! let signers = aggregator.signers();
 //! # Ok(()) }
 //! # fn main() { assert!(do_test().is_ok()); }
 //! ```
@@ -1530,7 +1530,7 @@
 //! # aggregator.include_signer(1, alice_public_comshares.commitments[0], &alice_public_key);
 //! # aggregator.include_signer(3, carol_public_comshares.commitments[0], &carol_public_key);
 //! #
-//! # let signers = aggregator.get_signers();
+//! # let signers = aggregator.signers();
 //! # let message_hash = Secp256k1Sha256::h4(&message[..]);
 //!
 //! let alice_partial = alice_secret_key.sign(