refactor coinselector to work with UTXO objects

src/_tests/unit/coinselection.unit.test.ts

@@ -1,16 +1,20 @@
 import assert from 'assert';
 import { FewestCoinSelector } from '../../transaction/coinselector-fewest.js';
-import { UTXOLike, denominations } from '../../transaction/utxo.js';
+import { UTXO, denominations } from '../../transaction/utxo.js';
 
 const TEST_SPEND_ADDRESS = '0x00539bc2CE3eD0FD039c582CB700EF5398bB0491';
 const TEST_RECEIVE_ADDRESS = '0x02b9B1D30B6cCdc7d908B82739ce891463c3FA19';
 
 // Utility function to create UTXOs (adjust as necessary)
-function createUTXOs(denominationIndices: number[]): UTXOLike[] {
-    return denominationIndices.map((index) => ({
-        denomination: index,
-        address: TEST_SPEND_ADDRESS,
-    }));
+function createUTXOs(denominationIndices: number[]): UTXO[] {
+    return denominationIndices.map((index) =>
+        UTXO.from({
+            txhash: '0x0000000000000000000000000000000000000000000000000000000000000000',
+            index: 0,
+            address: TEST_SPEND_ADDRESS,
+            denomination: index,
+        }),
+    );
 }
 
 describe('FewestCoinSelector', function () {

src/transaction/abstract-coinselector.ts

@@ -1,7 +1,8 @@
-import { UTXO, UTXOEntry, UTXOLike } from './utxo.js';
+import { UTXO, UTXOLike } from './utxo.js';
 
 /**
  * Represents a target for spending.
+ *
  * @typedef {Object} SpendTarget
  * @property {string} address - The address to send to.
  * @property {bigint} value - The amount to send.
@@ -13,6 +14,7 @@ export type SpendTarget = {
 
 /**
  * Represents the result of selected coins.
+ *
  * @typedef {Object} SelectedCoinsResult
  * @property {UTXO[]} inputs - The selected UTXOs.
  * @property {UTXO[]} spendOutputs - The outputs for spending.
@@ -36,24 +38,26 @@ export type SelectedCoinsResult = {
  * @abstract
  */
 export abstract class AbstractCoinSelector {
-    #availableUXTOs: UTXO[];
+    #availableUTXOs: UTXO[];
     #spendOutputs: UTXO[];
     #changeOutputs: UTXO[];
 
     /**
      * Gets the available UTXOs.
+     *
      * @returns {UTXO[]} The available UTXOs.
      */
-    get availableUXTOs(): UTXO[] {
-        return this.#availableUXTOs;
+    get availableUTXOs(): UTXO[] {
+        return this.#availableUTXOs;
     }
 
     /**
      * Sets the available UTXOs.
+     *
      * @param {UTXOLike[]} value - The UTXOs to set.
      */
-    set availableUXTOs(value: UTXOLike[]) {
-        this.#availableUXTOs = value.map((val) => {
+    set availableUTXOs(value: UTXOLike[]) {
+        this.#availableUTXOs = value.map((val) => {
             const utxo = UTXO.from(val);
             this._validateUTXO(utxo);
             return utxo;
@@ -62,6 +66,7 @@ export abstract class AbstractCoinSelector {
 
     /**
      * Gets the spend outputs.
+     *
      * @returns {UTXO[]} The spend outputs.
      */
     get spendOutputs(): UTXO[] {
@@ -70,6 +75,7 @@ export abstract class AbstractCoinSelector {
 
     /**
      * Sets the spend outputs.
+     *
      * @param {UTXOLike[]} value - The spend outputs to set.
      */
     set spendOutputs(value: UTXOLike[]) {
@@ -78,6 +84,7 @@ export abstract class AbstractCoinSelector {
 
     /**
      * Gets the change outputs.
+     *
      * @returns {UTXO[]} The change outputs.
      */
     get changeOutputs(): UTXO[] {
@@ -86,6 +93,7 @@ export abstract class AbstractCoinSelector {
 
     /**
      * Sets the change outputs.
+     *
      * @param {UTXOLike[]} value - The change outputs to set.
      */
     set changeOutputs(value: UTXOLike[]) {
@@ -94,11 +102,11 @@ export abstract class AbstractCoinSelector {
 
     /**
      * Constructs a new AbstractCoinSelector instance with an empty UTXO array.
-     * @param {UTXOEntry[]} [availableUXTOs=[]] - The initial available UTXOs.
+     *
+     * @param {UTXOEntry[]} [availableUXTOs=[]] - The initial available UTXOs. Default is `[]`
      */
-    constructor(availableUXTOs: UTXOEntry[] = []) {
-        this.#availableUXTOs = availableUXTOs.map((val: UTXOLike) => {
-            const utxo = UTXO.from(val);
+    constructor(availableUTXOs: UTXO[] = []) {
+        this.#availableUTXOs = availableUTXOs.map((utxo: UTXO) => {
             this._validateUTXO(utxo);
             return utxo;
         });
@@ -111,9 +119,9 @@ export abstract class AbstractCoinSelector {
      * UTXOs from the available UTXOs that sum to the target amount and return the selected UTXOs as well as the spend
      * and change outputs.
      *
+     * @abstract
      * @param {SpendTarget} target - The target address and value to spend.
      * @returns {SelectedCoinsResult} The selected UTXOs and outputs.
-     * @abstract
      */
     abstract performSelection(target: SpendTarget): SelectedCoinsResult;
 
@@ -133,5 +141,13 @@ export abstract class AbstractCoinSelector {
         if (utxo.denomination == null) {
             throw new Error('UTXO denomination is required');
         }
+
+        if (utxo.txhash == null) {
+            throw new Error('UTXO txhash is required');
+        }
+
+        if (utxo.index == null) {
+            throw new Error('UTXO index is required');
+        }
     }
 }

src/transaction/coinselector-fewest.ts

@@ -27,7 +27,7 @@ export class FewestCoinSelector extends AbstractCoinSelector {
         this.validateTarget(target);
         this.validateUTXOs();
 
-        const sortedUTXOs = this.sortUTXOsByDenomination(this.availableUXTOs, 'desc');
+        const sortedUTXOs = this.sortUTXOsByDenomination(this.availableUTXOs, 'desc');
 
         let totalValue = BigInt(0);
         let selectedUTXOs: UTXO[] = [];
@@ -78,34 +78,37 @@ export class FewestCoinSelector extends AbstractCoinSelector {
             }
         }
 
-        // Check if the selected UTXOs meet or exceed the target amount
-        if (totalValue < target.value) {
-            throw new Error('Insufficient funds');
-        }
-
-        // Check if any denominations can be removed from the input set and it still remain valid
-        selectedUTXOs = this.sortUTXOsByDenomination(selectedUTXOs, 'asc');
-
+        // Replace the existing optimization code with this new implementation
+        selectedUTXOs = this.sortUTXOsByDenomination(selectedUTXOs, 'desc');
         let runningTotal = totalValue;
-        let lastRemovableIndex = -1; // Index of the last UTXO that can be removed
 
-        // Iterate through selectedUTXOs to find the last removable UTXO
-        for (let i = 0; i < selectedUTXOs.length; i++) {
+        for (let i = selectedUTXOs.length - 1; i >= 0; i--) {
             const utxo = selectedUTXOs[i];
-            if (utxo.denomination !== null) {
-                if (runningTotal - denominations[utxo.denomination] >= target.value) {
-                    runningTotal -= denominations[utxo.denomination];
-                    lastRemovableIndex = i;
-                } else {
-                    // Once a UTXO makes the total less than target.value, stop the loop
-                    break;
-                }
+            if (utxo.denomination !== null && runningTotal - denominations[utxo.denomination] >= target.value) {
+                runningTotal -= denominations[utxo.denomination];
+                selectedUTXOs.splice(i, 1);
+            } else {
+                break;
             }
         }
 
-        if (lastRemovableIndex >= 0) {
-            totalValue -= denominations[selectedUTXOs[lastRemovableIndex].denomination!];
-            selectedUTXOs.splice(lastRemovableIndex, 1);
+        totalValue = runningTotal;
+
+        // Ensure that selectedUTXOs contain all required properties
+        const completeSelectedUTXOs = selectedUTXOs.map((utxo) => {
+            const originalUTXO = this.availableUTXOs.find(
+                (availableUTXO) =>
+                    availableUTXO.denomination === utxo.denomination && availableUTXO.address === utxo.address,
+            );
+            if (!originalUTXO) {
+                throw new Error('Selected UTXO not found in available UTXOs');
+            }
+            return originalUTXO;
+        });
+
+        // Check if the selected UTXOs meet or exceed the target amount
+        if (totalValue < target.value) {
+            throw new Error('Insufficient funds');
         }
 
         // Break down the total spend into properly denominatated UTXOs
@@ -134,7 +137,7 @@ export class FewestCoinSelector extends AbstractCoinSelector {
         }
 
         return {
-            inputs: selectedUTXOs,
+            inputs: completeSelectedUTXOs,
             spendOutputs: this.spendOutputs,
             changeOutputs: this.changeOutputs,
         };
@@ -182,7 +185,7 @@ export class FewestCoinSelector extends AbstractCoinSelector {
      * @throws Will throw an error if there are no available UTXOs.
      */
     private validateUTXOs() {
-        if (this.availableUXTOs.length === 0) {
+        if (this.availableUTXOs.length === 0) {
             throw new Error('No UTXOs available');
         }
     }