fix: improve BN unsafe numbers error handling (#3636)

Author: Torres-ssf

.changeset/sweet-walls-wonder.md

@@ -0,0 +1,6 @@
+---
+"@fuel-ts/errors": patch
+"@fuel-ts/math": patch
+---
+
+fix: improve BN unsafe numbers error handling

packages/account/src/account.test.ts

@@ -999,4 +999,19 @@ describe('Account', () => {
       expect([baseAssetId, ASSET_A, ASSET_B].includes(balance.assetId)).toBeTruthy();
     });
   });
+
+  test('can ensure using unsafe numbers throws proper error', async () => {
+    using launched = await setupTestProviderAndWallets();
+    const {
+      wallets: [wallet],
+      provider,
+    } = launched;
+
+    const baseAssetId = await provider.getBaseAssetId();
+
+    await expectToThrowFuelError(
+      () => wallet.transfer(wallet.address, Number.MAX_SAFE_INTEGER + 1, baseAssetId),
+      { code: ErrorCode.NUMBER_TOO_BIG }
+    );
+  });
 });

packages/errors/src/error-codes.ts

@@ -103,6 +103,9 @@ export enum ErrorCode {
   ACCOUNT_REQUIRED = 'account-required',
   UNLOCKED_WALLET_REQUIRED = 'unlocked-wallet-required',
 
+  // bn
+  NUMBER_TOO_BIG = 'number-too-big',
+
   // chain
   ERROR_BUILDING_BLOCK_EXPLORER_URL = 'error-building-block-explorer-url',
 

packages/math/src/bn.test.ts

@@ -1,3 +1,6 @@
+import { FuelError, ErrorCode } from '@fuel-ts/errors';
+import { expectToThrowFuelError } from '@fuel-ts/errors/test-utils';
+
 import type { BN } from './bn';
 import { bn } from './bn';
 import type { BigNumberish } from './types';
@@ -111,6 +114,18 @@ describe('Math - BN', () => {
     expect(bn(numberToConvert).toHex()).toEqual(hexToConvert);
   });
 
+  it('should convert safe numbers', () => {
+    let number = Number.MAX_SAFE_INTEGER;
+    let expectedHex = '0x1fffffffffffff';
+    expect(bn(number).toNumber()).toEqual(number);
+    expect(bn(number).toHex()).toEqual(expectedHex);
+
+    number = Number.MAX_SAFE_INTEGER - 0.5;
+    expectedHex = '0x1ffffffffffffe';
+    expect(bn(number).toNumber()).toEqual(number);
+    expect(bn(number).toHex()).toEqual(expectedHex);
+  });
+
   it('should toHex accept bytePadding config', () => {
     let numberToConvert: number;
     let bytesToConvert: Uint8Array;
@@ -541,4 +556,18 @@ describe('Math - BN', () => {
   it('should return significant figures even if it exceeds the precision', () => {
     expect(bn('4000000').format({ precision: 1 })).toEqual('0.004');
   });
+
+  it('should throws expected error when using unsafe numbers', async () => {
+    const unsafeNumbers = [Number.MAX_SAFE_INTEGER + 1, Number.MAX_SAFE_INTEGER + 1.1];
+
+    for (const unsafeNumber of unsafeNumbers) {
+      await expectToThrowFuelError(
+        () => bn(unsafeNumber),
+        new FuelError(
+          ErrorCode.NUMBER_TOO_BIG,
+          `Value ${unsafeNumber} is too large to be represented as a number, use string instead.`
+        )
+      );
+    }
+  });
 });

packages/math/src/bn.ts

@@ -57,6 +57,13 @@ export class BN extends BnJs implements BNInputOverrides, BNHiddenTypes, BNHelpe
       bnBase = base || 'hex';
     }
 
+    if (typeof bnValue === 'number' && bnValue > Number.MAX_SAFE_INTEGER) {
+      throw new FuelError(
+        ErrorCode.NUMBER_TOO_BIG,
+        `Value ${bnValue} is too large to be represented as a number, use string instead.`
+      );
+    }
+
     super(bnValue == null ? 0 : bnValue, bnBase, endian);
   }