fix: calculate transaction fee (#1102)

.changeset/serious-pans-search.md

@@ -0,0 +1,5 @@
+---
+"@fuel-ts/providers": minor
+---
+
+Fix incorrect gasUsed and fee calculation in calculateTransactionFee function

packages/providers/src/operations.graphql

@@ -173,6 +173,13 @@ query getInfo {
     nodeVersion
     minGasPrice
   }
+  chain {
+    consensusParameters {
+      gasPerByte
+      maxGasPerTx
+      gasPriceFactor
+    }
+  }
 }
 
 query getChain {

packages/providers/src/provider.ts

@@ -15,7 +15,6 @@ import {
   ReceiptCoder,
   TransactionCoder,
 } from '@fuel-ts/transactions';
-import { MAX_GAS_PER_TX } from '@fuel-ts/transactions/configs';
 import { GraphQLClient } from 'graphql-request';
 import cloneDeep from 'lodash.clonedeep';
 
@@ -102,9 +101,12 @@ export type ChainInfo = {
 /**
  * Node information
  */
-export type NodeInfo = {
+export type NodeInfoAndConsensusParameters = {
   minGasPrice: BN;
   nodeVersion: string;
+  gasPerByte: BN;
+  gasPriceFactor: BN;
+  maxGasPerTx: BN;
 };
 
 // #region cost-estimation-1
@@ -172,9 +174,15 @@ const processGqlChain = (chain: GqlChainInfoFragmentFragment): ChainInfo => {
   };
 };
 
-const processNodeInfo = (nodeInfo: GqlGetInfoQuery['nodeInfo']) => ({
+const processNodeInfoAndConsensusParameters = (
+  nodeInfo: GqlGetInfoQuery['nodeInfo'],
+  consensusParameters: GqlGetInfoQuery['chain']['consensusParameters']
+) => ({
   minGasPrice: bn(nodeInfo.minGasPrice),
   nodeVersion: nodeInfo.nodeVersion,
+  gasPerByte: bn(consensusParameters.gasPerByte),
+  gasPriceFactor: bn(consensusParameters.gasPriceFactor),
+  maxGasPerTx: bn(consensusParameters.maxGasPerTx),
 });
 
 /**
@@ -280,9 +288,9 @@ export default class Provider {
   /**
    * Returns node information
    */
-  async getNodeInfo(): Promise<NodeInfo> {
-    const { nodeInfo } = await this.operations.getInfo();
-    return processNodeInfo(nodeInfo);
+  async getNodeInfo(): Promise<NodeInfoAndConsensusParameters> {
+    const { nodeInfo, chain } = await this.operations.getInfo();
+    return processNodeInfoAndConsensusParameters(nodeInfo, chain.consensusParameters);
   }
 
   /**
@@ -487,22 +495,29 @@ export default class Provider {
     tolerance: number = 0.2
   ): Promise<TransactionCost> {
     const transactionRequest = transactionRequestify(cloneDeep(transactionRequestLike));
-    const { minGasPrice } = await this.getNodeInfo();
+    const { minGasPrice, gasPerByte, gasPriceFactor, maxGasPerTx } = await this.getNodeInfo();
     const gasPrice = max(transactionRequest.gasPrice, minGasPrice);
     const margin = 1 + tolerance;
 
     // Set gasLimit to the maximum of the chain
     // and gasPrice to 0 for measure
     // Transaction without arrive to OutOfGas
-    transactionRequest.gasLimit = MAX_GAS_PER_TX;
+    transactionRequest.gasLimit = maxGasPerTx;
     transactionRequest.gasPrice = bn(0);
 
     // Execute dryRun not validated transaction to query gasUsed
     const { receipts } = await this.call(transactionRequest);
+    const transaction = transactionRequest.toTransaction();
+
     const { gasUsed, fee } = calculateTransactionFee({
       gasPrice,
       receipts,
       margin,
+      gasPerByte,
+      gasPriceFactor,
+      transactionBytes: transactionRequest.toTransactionBytes(),
+      transactionType: transactionRequest.type,
+      transactionWitnesses: transaction.witnesses,
     });
 
     return {

packages/providers/src/transaction-response/transaction-response.ts

@@ -16,6 +16,7 @@ import type {
   ReceiptScriptResult,
   ReceiptMessageOut,
   Transaction,
+  TransactionCreate,
 } from '@fuel-ts/transactions';
 import { TransactionCoder, ReceiptType, ReceiptCoder } from '@fuel-ts/transactions';
 
@@ -143,9 +144,16 @@ export class TransactionResponse {
       }
       case 'FailureStatus': {
         const receipts = transactionWithReceipts.receipts!.map(processGqlReceipt);
+
+        const decodedTransaction =
+          this.decodeTransaction<TTransactionType>(transactionWithReceipts);
+
         const { gasUsed, fee } = calculateTransactionFee({
           receipts,
           gasPrice: bn(transactionWithReceipts?.gasPrice),
+          transactionBytes: arrayify(transactionWithReceipts.rawPayload),
+          transactionType: decodedTransaction.type,
+          transactionWitnesses: (<TransactionCreate>decodedTransaction).witnesses || [],
         });
 
         this.gasUsed = gasUsed;
@@ -157,14 +165,21 @@ export class TransactionResponse {
           time: transactionWithReceipts.status.time,
           gasUsed,
           fee,
-          transaction: this.decodeTransaction(transactionWithReceipts),
+          transaction: decodedTransaction,
         };
       }
       case 'SuccessStatus': {
         const receipts = transactionWithReceipts.receipts?.map(processGqlReceipt) || [];
+
+        const decodedTransaction =
+          this.decodeTransaction<TTransactionType>(transactionWithReceipts);
+
         const { gasUsed, fee } = calculateTransactionFee({
           receipts,
           gasPrice: bn(transactionWithReceipts?.gasPrice),
+          transactionBytes: arrayify(transactionWithReceipts.rawPayload),
+          transactionType: decodedTransaction.type,
+          transactionWitnesses: (<TransactionCreate>decodedTransaction).witnesses || [],
         });
 
         return {
@@ -175,7 +190,7 @@ export class TransactionResponse {
           time: transactionWithReceipts.status.time,
           gasUsed,
           fee,
-          transaction: this.decodeTransaction(transactionWithReceipts),
+          transaction: decodedTransaction,
         };
       }
       default: {

packages/providers/src/utils/fee.test.ts

@@ -0,0 +1,143 @@
+import { BN } from '@fuel-ts/math';
+import { ReceiptType, type Witness } from '@fuel-ts/transactions';
+
+import type { TransactionResultReceipt } from '../transaction-response';
+
+import {
+  calculatePriceWithFactor,
+  getGasUsedForContractCreated,
+  getGasUsedFromReceipts,
+} from './fee';
+
+describe(__filename, () => {
+  describe('calculatePriceWithFactor', () => {
+    it('should correctly calculate the price with factor', () => {
+      const gasUsed = new BN(10);
+      const gasPrice = new BN(2);
+      const priceFactor = new BN(5);
+
+      const result = calculatePriceWithFactor(gasUsed, gasPrice, priceFactor);
+
+      expect(result.toNumber()).toEqual(4); // ceil(10 / 5) * 2 = 4
+    });
+
+    it('should correctly round up the result', () => {
+      const gasUsed = new BN(11);
+      const gasPrice = new BN(2);
+      const priceFactor = new BN(5);
+
+      const result = calculatePriceWithFactor(gasUsed, gasPrice, priceFactor);
+
+      expect(result.toNumber()).toEqual(6); // ceil(11 / 5) * 2 = 6
+    });
+  });
+
+  describe('getGasUsedForContractCreated', () => {
+    it('should calculate gas used for contract created correctly', () => {
+      const transactionBytes = new Uint8Array([0, 1, 2, 3, 4, 5]);
+      const gasPerByte = new BN(1);
+      const gasPriceFactor = new BN(2);
+      const transactionWitnesses: Witness[] = [{ dataLength: 2, data: 'data' }];
+
+      const result = getGasUsedForContractCreated({
+        transactionBytes,
+        gasPerByte,
+        gasPriceFactor,
+        transactionWitnesses,
+      });
+
+      expect(result.toNumber()).toEqual(2); // (6-2)*1/2 = 2
+    });
+
+    it('should handle an empty witnesses array', () => {
+      const transactionBytes = new Uint8Array([0, 1, 2, 3, 4, 5]);
+      const gasPerByte = new BN(1);
+      const gasPriceFactor = new BN(2);
+      const transactionWitnesses: Witness[] = [];
+
+      const result = getGasUsedForContractCreated({
+        transactionBytes,
+        gasPerByte,
+        gasPriceFactor,
+        transactionWitnesses,
+      });
+
+      expect(result.toNumber()).toEqual(3); // 6*1/2 = 3
+    });
+
+    it('should round up the result', () => {
+      const transactionBytes = new Uint8Array([0, 1, 2]);
+      const gasPerByte = new BN(1);
+      const gasPriceFactor = new BN(2);
+      const transactionWitnesses: Witness[] = [];
+
+      const result = getGasUsedForContractCreated({
+        transactionBytes,
+        gasPerByte,
+        gasPriceFactor,
+        transactionWitnesses,
+      });
+
+      expect(result.toNumber()).toEqual(2); // 3*1/2 = 1.5 which rounds up to 2
+    });
+  });
+
+  describe('getGasUsedFromReceipts', () => {
+    it('should return correct total gas used from ScriptResult receipts', () => {
+      const receipts: Array<TransactionResultReceipt> = [
+        {
+          type: ReceiptType.Return,
+          id: '0xbebd3baab326f895289ecbd4210cf886ce41952316441ae4cac35f00f0e882a6',
+          val: new BN(1),
+          pc: new BN(2),
+          is: new BN(3),
+        },
+        {
+          type: ReceiptType.ScriptResult,
+          result: new BN(4),
+          gasUsed: new BN(5),
+        },
+        {
+          type: ReceiptType.ScriptResult,
+          result: new BN(6),
+          gasUsed: new BN(7),
+        },
+      ];
+
+      const result = getGasUsedFromReceipts(receipts);
+
+      expect(result.toNumber()).toEqual(12); // 5 + 7 = 12
+    });
+
+    it('should return zero if there are no ScriptResult receipts', () => {
+      const receipts: Array<TransactionResultReceipt> = [
+        {
+          type: ReceiptType.Return,
+          id: '0xbebd3baab326f895289ecbd4210cf886ce41952316441ae4cac35f00f0e882a6',
+          val: new BN(1),
+          pc: new BN(2),
+          is: new BN(3),
+        },
+        {
+          type: ReceiptType.Return,
+          id: '0xa703b26833939dabc41d3fcaefa00e62cee8e1ac46db37e0fa5d4c9fe30b4132',
+          val: new BN(4),
+          pc: new BN(5),
+          is: new BN(6),
+        },
+      ];
+
+      const result = getGasUsedFromReceipts(receipts);
+
+      expect(result.toNumber()).toEqual(0);
+    });
+
+    it('should return zero if the receipts array is empty', () => {
+      const receipts: Array<TransactionResultReceipt> = [];
+
+      const result = getGasUsedFromReceipts(receipts);
+
+      expect(result.toNumber()).toEqual(0);
+    });
+  });
+});