#prefer-bigint-literals

#Configuration

import { defineConfig, unicornPlugin } from '@rslint/core';

export default defineConfig([
  unicornPlugin.configs.recommended,
  {
    rules: {
      'unicorn/prefer-bigint-literals': 'error',
    },
  },
]);

#Rule details

Prefer a bigint literal when the argument to the built-in BigInt() function is an integer number or a string that can be converted to a bigint. The rule checks quoted strings, templates without substitutions, and numeric literals with unary + or -.

Examples of incorrect code for this rule

const bigint = BigInt(1);
const large = BigInt('9007199254740991');
const hex = BigInt('0xFF');

Examples of correct code for this rule

const bigint = 1n;
const large = 9007199254740991n;
const hex = 0xFFn;
const computed = BigInt(getSomeNumber());
const astronomicalNumber = 999999999999999999999999n;

The rule offers editor suggestions for calls that contain comments or an explicit + sign. It also offers a suggestion when a numeric argument needs a different spelling as a bigint literal, as in BigInt(1e2) becoming 100n.

#Options

This rule has no options.

#Differences from upstream

• Rslint skips calls where a local binding or a with statement can supply another BigInt function. It also skips calls with TypeScript type arguments or when languageOptions.globals disables BigInt.
• Keep the call when the configured ECMAScript version predates ES2020. Rslint also skips TypeScript files with a build target older than ES2020.
• BigInt(1000000000000000100) suggests 1000000000000000128n to preserve the value of the call after JavaScript rounds the numeric argument.
• Fixes add spaces where compact code would otherwise run together. For example, BigInt(1)in object becomes 1n in object.
• Rslint rejects the legacy spellings in BigInt(0777) and BigInt(0888) even in scripts. Write 511n and 888n for those values.

#Original documentation

• eslint-plugin-unicorn: prefer-bigint-literals
• Source code