Add cost_of_change to coin_select parameters

Author: csralvall

src/wallet/coin_selection.rs

@@ -42,6 +42,7 @@
 //!         fee_rate: FeeRate,
 //!         amount_needed: u64,
 //!         fee_amount: u64,
+//!         cost_of_change: Option<u64>,
 //!     ) -> Result<CoinSelectionResult, bdk::Error> {
 //!         let mut selected_amount = 0;
 //!         let mut additional_weight = 0;
@@ -238,6 +239,7 @@ pub trait CoinSelectionAlgorithm<D: Database>: std::fmt::Debug {
         fee_rate: FeeRate,
         amount_needed: u64,
         fee_amount: u64,
+        cost_of_change: Option<u64>,
     ) -> Result<CoinSelectionResult, Error>;
 }
 
@@ -257,6 +259,7 @@ impl<D: Database> CoinSelectionAlgorithm<D> for LargestFirstCoinSelection {
         fee_rate: FeeRate,
         amount_needed: u64,
         fee_amount: u64,
+        cost_of_change: Option<u64>,
     ) -> Result<CoinSelectionResult, Error> {
         log::debug!(
             "amount_needed = `{}`, fee_amount = `{}`, fee_rate = `{:?}`",
@@ -295,6 +298,7 @@ impl<D: Database> CoinSelectionAlgorithm<D> for OldestFirstCoinSelection {
         fee_rate: FeeRate,
         amount_needed: u64,
         fee_amount: u64,
+        cost_of_change: Option<u64>,
     ) -> Result<CoinSelectionResult, Error> {
         // query db and create a blockheight lookup table
         let blockheights = optional_utxos
@@ -437,6 +441,7 @@ impl<D: Database> CoinSelectionAlgorithm<D> for BranchAndBoundCoinSelection {
         fee_rate: FeeRate,
         amount_needed: u64,
         fee_amount: u64,
+        cost_of_change: Option<u64>,
     ) -> Result<CoinSelectionResult, Error> {
         // Mapping every (UTXO, usize) to an output group
         let required_utxos: Vec<OutputGroup<'_>> = required_utxos
@@ -857,6 +862,7 @@ mod test {
                 FeeRate::from_sat_per_vb(1.0),
                 250_000,
                 FEE_AMOUNT,
+                None,
             )
             .unwrap();
 
@@ -878,6 +884,7 @@ mod test {
                 FeeRate::from_sat_per_vb(1.0),
                 20_000,
                 FEE_AMOUNT,
+                None,
             )
             .unwrap();
 
@@ -899,6 +906,7 @@ mod test {
                 FeeRate::from_sat_per_vb(1.0),
                 20_000,
                 FEE_AMOUNT,
+                None,
             )
             .unwrap();
 
@@ -921,6 +929,7 @@ mod test {
                 FeeRate::from_sat_per_vb(1.0),
                 500_000,
                 FEE_AMOUNT,
+                None,
             )
             .unwrap();
     }
@@ -939,6 +948,7 @@ mod test {
                 FeeRate::from_sat_per_vb(1000.0),
                 250_000,
                 FEE_AMOUNT,
+                None,
             )
             .unwrap();
     }
@@ -956,6 +966,7 @@ mod test {
                 FeeRate::from_sat_per_vb(1.0),
                 180_000,
                 FEE_AMOUNT,
+                None,
             )
             .unwrap();
 
@@ -1012,6 +1023,7 @@ mod test {
                 FeeRate::from_sat_per_vb(1.0),
                 180_000,
                 FEE_AMOUNT,
+                None,
             )
             .unwrap();
 
@@ -1033,6 +1045,7 @@ mod test {
                 FeeRate::from_sat_per_vb(1.0),
                 20_000,
                 FEE_AMOUNT,
+                None,
             )
             .unwrap();
 
@@ -1054,6 +1067,7 @@ mod test {
                 FeeRate::from_sat_per_vb(1.0),
                 20_000,
                 FEE_AMOUNT,
+                None,
             )
             .unwrap();
 
@@ -1076,6 +1090,7 @@ mod test {
                 FeeRate::from_sat_per_vb(1.0),
                 600_000,
                 FEE_AMOUNT,
+                None,
             )
             .unwrap();
     }
@@ -1097,6 +1112,7 @@ mod test {
                 FeeRate::from_sat_per_vb(1000.0),
                 amount_needed,
                 FEE_AMOUNT,
+                None,
             )
             .unwrap();
     }
@@ -1117,6 +1133,7 @@ mod test {
                 FeeRate::from_sat_per_vb(1.0),
                 250_000,
                 FEE_AMOUNT,
+                None,
             )
             .unwrap();
 
@@ -1138,6 +1155,7 @@ mod test {
                 FeeRate::from_sat_per_vb(1.0),
                 20_000,
                 FEE_AMOUNT,
+                None,
             )
             .unwrap();
 
@@ -1159,6 +1177,7 @@ mod test {
                 FeeRate::from_sat_per_vb(1.0),
                 299756,
                 FEE_AMOUNT,
+                None,
             )
             .unwrap();
 
@@ -1190,6 +1209,7 @@ mod test {
                 FeeRate::from_sat_per_vb(1.0),
                 150_000,
                 FEE_AMOUNT,
+                None,
             )
             .unwrap();
 
@@ -1212,6 +1232,7 @@ mod test {
                 FeeRate::from_sat_per_vb(1.0),
                 500_000,
                 FEE_AMOUNT,
+                None,
             )
             .unwrap();
     }
@@ -1230,6 +1251,7 @@ mod test {
                 FeeRate::from_sat_per_vb(1000.0),
                 250_000,
                 FEE_AMOUNT,
+                None,
             )
             .unwrap();
     }
@@ -1247,6 +1269,7 @@ mod test {
                 FeeRate::from_sat_per_vb(1.0),
                 99932, // first utxo's effective value
                 0,
+                None,
             )
             .unwrap();
 
@@ -1274,6 +1297,7 @@ mod test {
                     FeeRate::from_sat_per_vb(0.0),
                     target_amount,
                     0,
+                    None,
                 )
                 .unwrap();
             assert_eq!(result.selected_amount(), target_amount);

src/wallet/mod.rs

@@ -751,6 +751,8 @@ where
             fee_rate,
             outgoing,
             fee_amount,
+            // REVIEW: Add cost_of_change to TxParams
+            None,
         )?;
         let mut fee_amount = coin_selection.fee_amount;