refactor(wallet): cleanup and remove unused code in create_tx

crates/wallet/src/wallet/mod.rs

@@ -70,7 +70,7 @@ use crate::types::*;
 use crate::wallet::{
     coin_selection::{
         DefaultCoinSelectionAlgorithm,
-        Excess::{self, Change, NoChange},
+        Excess::{Change, NoChange},
         InsufficientFunds,
     },
     error::{BuildFeeBumpError, CreateTxError, MiniscriptPsbtError},
@@ -1461,9 +1461,8 @@ impl Wallet {
                 rng,
             )
             .map_err(CreateTxError::CoinSelection)?;
-        fee_amount += Amount::from_sat(coin_selection.fee_amount);
-        let excess = &coin_selection.excess;
 
+        let excess = &coin_selection.excess;
         tx.input = coin_selection
             .selected
             .iter()
@@ -1500,36 +1499,27 @@ impl Wallet {
             }
         }
 
-        match excess {
-            NoChange {
-                remaining_amount, ..
-            } => fee_amount += Amount::from_sat(*remaining_amount),
-            Change { amount, fee } => {
-                if self.is_mine(drain_script.clone()) {
-                    received += Amount::from_sat(*amount);
-                }
-                fee_amount += Amount::from_sat(*fee);
-
-                // create drain output
-                let drain_output = TxOut {
-                    value: Amount::from_sat(*amount),
-                    script_pubkey: drain_script,
-                };
+        // if there's change, create and add a change output
+        if let Change { amount, .. } = excess {
+            // create drain output
+            let drain_output = TxOut {
+                value: Amount::from_sat(*amount),
+                script_pubkey: drain_script,
+            };
 
-                // TODO: We should pay attention when adding a new output: this might increase
-                // the length of the "number of vouts" parameter by 2 bytes, potentially making
-                // our feerate too low
-                tx.output.push(drain_output);
-            }
-        };
+            // TODO: We should pay attention when adding a new output: this might increase
+            // the length of the "number of vouts" parameter by 2 bytes, potentially making
+            // our feerate too low
+            tx.output.push(drain_output);
+        }
 
         // sort input/outputs according to the chosen algorithm
         params.ordering.sort_tx_with_aux_rand(&mut tx, rng);
 
         let psbt = self.complete_transaction(tx, coin_selection.selected, params)?;
 
         // recording changes to the change keychain
-        if let (Excess::Change { .. }, Some((keychain, index))) = (excess, drain_index) {
+        if let (Change { .. }, Some((keychain, index))) = (excess, drain_index) {
             let (_, index_changeset) = self
                 .indexed_graph
                 .index