feat: using gas modifier at Provider.getTransactionCost (#3319)

* using a gas used modifier * refact code * add test case * add changeset * update tests * adjusting test * adjust test * add new BN helper * validate max gas per tx * fix changeset * using modifier of 20% * update test name --------- Co-authored-by: Anderson Arboleya <[email protected]>
FuelLabs · Oct 14, 2024 · 987aed3 · 987aed3
1 parent eb3b6c9
commit 987aed3
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Showing 8 changed files with 60 additions and 6 deletions.
diff --git a/.changeset/yellow-toes-smell.md b/.changeset/yellow-toes-smell.md
@@ -0,0 +1,6 @@
+---
+"@fuel-ts/account": patch
+"@fuel-ts/math": patch
+---
+
+feat: using gas modifier at `Provider.getTransactionCost`
diff --git a/apps/docs-snippets/src/guide/scripts/script-with-configurable.test.ts b/apps/docs-snippets/src/guide/scripts/script-with-configurable.test.ts
@@ -49,7 +49,7 @@ describe('Script With Configurable', () => {
     const tx = script.functions.main(argument);
 
     // Set the call parameters
-    tx.callParams({ gasLimit: 1500 });
+    tx.callParams({ gasLimit: 1700 });
 
     // Get the entire transaction request prior to
     const txRequest = await tx.getTransactionRequest();

diff --git a/apps/docs-snippets2/src/transactions/transaction-parameters.ts b/apps/docs-snippets2/src/transactions/transaction-parameters.ts
@@ -16,7 +16,7 @@ const { contract } = await deploy.waitForResult();
 // #region transaction-parameters-6
 const txParams: TxParams = {
   // #region transaction-parameters-1
-  gasLimit: bn(69242),
+  gasLimit: bn(70935),
   // #endregion transaction-parameters-1
   // #region transaction-parameters-2
   maxFee: bn(69242),

diff --git a/packages/account/src/providers/provider.test.ts b/packages/account/src/providers/provider.test.ts
@@ -29,6 +29,7 @@ import type { ChainInfo, CursorPaginationArgs, NodeInfo } from './provider';
 import Provider, {
   BLOCKS_PAGE_SIZE_LIMIT,
   DEFAULT_RESOURCE_CACHE_TTL,
+  GAS_USED_MODIFIER,
   RESOURCES_PAGE_SIZE_LIMIT,
 } from './provider';
 import type { ExcludeResourcesOption } from './resource';
@@ -1374,6 +1375,27 @@ Supported fuel-core version: ${mock.supportedVersion}.`
     expect(minFee.eq(0)).not.toBeTruthy();
   });
 
+  it('should ensure gas used has a modifier', async () => {
+    using launched = await setupTestProviderAndWallets();
+
+    const {
+      provider,
+      wallets: [wallet],
+    } = launched;
+
+    const request = new ScriptTransactionRequest();
+    request.addCoinOutput(wallet.address, 1000, provider.getBaseAssetId());
+
+    const spyGetGasUsedFromReceipts = vi.spyOn(gasMod, 'getGasUsedFromReceipts');
+    const cost = await wallet.getTransactionCost(request);
+
+    const pristineGasUsed = spyGetGasUsedFromReceipts.mock.results[0].value;
+
+    expect(cost.gasUsed.toNumber()).toBe(
+      bn(pristineGasUsed.toNumber() * GAS_USED_MODIFIER).toNumber()
+    );
+  });
+
   it('should accept string addresses in methods that require an address', async () => {
     using launched = await setupTestProviderAndWallets();
     const { provider } = launched;

diff --git a/packages/account/src/providers/provider.ts b/packages/account/src/providers/provider.ts
@@ -69,6 +69,7 @@ export const RESOURCES_PAGE_SIZE_LIMIT = 512;
 export const TRANSACTIONS_PAGE_SIZE_LIMIT = 60;
 export const BLOCKS_PAGE_SIZE_LIMIT = 5;
 export const DEFAULT_RESOURCE_CACHE_TTL = 20_000; // 20 seconds
+export const GAS_USED_MODIFIER = 1.2;
 
 export type DryRunFailureStatusFragment = GqlDryRunFailureStatusFragment;
 export type DryRunSuccessStatusFragment = GqlDryRunSuccessStatusFragment;
@@ -1319,7 +1320,10 @@ Supported fuel-core version: ${supportedVersion}.`
         throw this.extractDryRunError(txRequestClone, receipts, dryRunStatus);
       }
 
-      gasUsed = getGasUsedFromReceipts(receipts);
+      const { maxGasPerTx } = this.getGasConfig();
+
+      const pristineGasUsed = getGasUsedFromReceipts(receipts);
+      gasUsed = bn(pristineGasUsed.muln(GAS_USED_MODIFIER)).max(maxGasPerTx.sub(minGas));
       txRequestClone.gasLimit = gasUsed;
 
       ({ maxFee, maxGas, minFee, minGas, gasPrice } = await this.estimateTxGasAndFee({

diff --git a/packages/fuel-gauge/src/min-gas.test.ts b/packages/fuel-gauge/src/min-gas.test.ts
@@ -7,6 +7,7 @@ import {
   getGasUsedFromReceipts,
   BigNumberCoder,
   ContractFactory,
+  GAS_USED_MODIFIER,
 } from 'fuels';
 import { launchTestNode } from 'fuels/test-utils';
 
@@ -103,7 +104,8 @@ describe('Minimum gas tests', () => {
     const { status, gasUsed: txGasUsed } = await result.wait();
 
     expect(status).toBe(TransactionStatus.success);
-    expect(txCost.gasUsed.toString()).toBe(txGasUsed.toString());
+    // Final gas is less then the estimated in a normal scenario
+    expect(txCost.gasUsed.toNumber()).toBe(txGasUsed.muln(GAS_USED_MODIFIER).toNumber());
   });
 
   it('sets gas requirements (predicate)', async () => {
@@ -152,7 +154,8 @@ describe('Minimum gas tests', () => {
     const gasUsedFromReceipts = getGasUsedFromReceipts(receipts);
 
     expect(status).toBe(TransactionStatus.success);
-    expect(txCost.gasUsed.toString()).toBe(gasUsedFromReceipts.toString());
+    // Final gas is less then the estimated in a normal scenario
+    expect(txCost.gasUsed.toNumber()).toBe(gasUsedFromReceipts.muln(GAS_USED_MODIFIER).toNumber());
   });
 
   it('sets gas requirements (account and predicate with script)', async () => {
@@ -221,6 +224,7 @@ describe('Minimum gas tests', () => {
     const txGasUsed = getGasUsedFromReceipts(receipts);
 
     expect(status).toBe(TransactionStatus.success);
-    expect(txCost.gasUsed.toString()).toBe(txGasUsed.toString());
+    // Final gas is less then the estimated in a normal scenario
+    expect(txCost.gasUsed.toNumber()).toBe(txGasUsed.muln(GAS_USED_MODIFIER).toNumber());
   });
 });
diff --git a/packages/math/src/bn.test.ts b/packages/math/src/bn.test.ts
@@ -255,6 +255,20 @@ describe('Math - BN', () => {
     expect(() => bn(over).toBytes(4)).toThrow();
   });
 
+  it('should ensure max method works just like expected', () => {
+    // Using Number
+    const maxNumber = 100_000;
+    const exceedingNumber = maxNumber + 1;
+
+    let maxSafeNumber = bn(exceedingNumber).max(maxNumber);
+
+    expect(maxSafeNumber.toNumber()).toEqual(maxNumber);
+
+    // Using BN
+    maxSafeNumber = bn(maxNumber).add(1).max(bn(maxNumber));
+    expect(maxSafeNumber.toNumber()).toEqual(maxNumber);
+  });
+
   it('should toHex break when value provided is bigger than bytePadding config', () => {
     let maxBytes: Uint8Array;
     let maxHex: string;

diff --git a/packages/math/src/bn.ts b/packages/math/src/bn.ts
@@ -307,6 +307,10 @@ export class BN extends BnJs implements BNInputOverrides, BNHiddenTypes, BNHelpe
     return this.gte(this.MAX_U64) ? new BN(this.MAX_U64) : this;
   }
 
+  max(num: BNInput): BN {
+    return this.gte(num) ? new BN(num) : this;
+  }
+
   normalizeZeroToOne(): BN {
     return this.isZero() ? new BN(1) : this;
   }