style change to the utxo module

signer/src/utxo.rs

@@ -112,12 +112,12 @@ impl DepositRequest {
     /// Create a TxIn object with witness data for the deposit script of
     /// the given request. Only a valid signature is needed to satisfy the
     /// deposit script.
-    fn as_tx_input(&self, sig: Signature) -> TxIn {
+    fn as_tx_input(&self, signature: Signature) -> TxIn {
         TxIn {
             previous_output: self.outpoint,
             script_sig: ScriptBuf::new(),
             sequence: Sequence(0),
-            witness: self.construct_witness_data(sig),
+            witness: self.construct_witness_data(signature),
         }
     }
 
@@ -135,7 +135,7 @@ impl DepositRequest {
     /// given by self.signers_public_key. The public key used for key-path
     /// spending is self.taproot_public_key, and is supposed to be a dummy
     /// public key.
-    pub fn construct_witness_data(&self, sig: Signature) -> Witness {
+    pub fn construct_witness_data(&self, signature: Signature) -> Witness {
         let (internal_key, _) = self.taproot_public_key.inner.x_only_public_key();
         let ver = LeafVersion::TapScript;
 
@@ -160,6 +160,7 @@ impl DepositRequest {
 
         let x_signers_public_key = self.signers_public_key.inner.x_only_public_key().0;
         let witness_data = [
+            signature.to_vec(),
             x_signers_public_key.serialize().to_vec(),
             self.deposit_script.to_bytes(),
             control_block.serialize(),
@@ -250,11 +251,11 @@ impl SignerUtxo {
     ///
     /// The signers' UTXO is always a key-spend only taproot UTXO, so a
     /// valid signature is all that is needed to spend it.
-    fn as_tx_input(&self, sig: &Signature) -> TxIn {
+    fn as_tx_input(&self, signature: &Signature) -> TxIn {
         TxIn {
             previous_output: self.outpoint,
             sequence: Sequence::ZERO,
-            witness: Witness::p2tr_key_spend(sig),
+            witness: Witness::p2tr_key_spend(signature),
             script_sig: ScriptBuf::new(),
         }
     }
@@ -333,16 +334,16 @@ impl<'a> UnsignedTransaction<'a> {
     /// An Err is returned if the amounts withdrawn is greater than the sum
     /// of all the input amounts.
     fn new_transaction(reqs: &[Request], state: &SignerBtcState) -> Result<Transaction, Error> {
-        let sig = Self::generate_dummy_signature();
+        let signature = Self::generate_dummy_signature();
 
         let deposits = reqs
             .iter()
-            .filter_map(|req| Some(req.as_deposit()?.as_tx_input(sig)));
+            .filter_map(|req| Some(req.as_deposit()?.as_tx_input(signature)));
         let withdrawals = reqs
             .iter()
             .filter_map(|req| Some(req.as_withdrawal()?.as_tx_output()));
 
-        let signer_input = state.utxo.as_tx_input(&sig);
+        let signer_input = state.utxo.as_tx_input(&signature);
         let signer_output_sats = Self::compute_signer_amount(reqs, state)?;
         let signer_output = SignerUtxo::new_tx_output(state.public_key, signer_output_sats);