eslint-plugin-unicorn/rules/number-literal-case.js

Various awesome ESLint rules

'use strict';
const {checkVueTemplate} = require('./utils/rule.js');
const {isNumber, isBigInt} = require('./utils/numeric.js');

const MESSAGE_ID = 'number-literal-case';
const messages = {
	[MESSAGE_ID]: 'Invalid number literal casing.',
};

const fix = raw => {
	let fixed = raw.toLowerCase();
	if (fixed.startsWith('0x')) {
		fixed = '0x' + fixed.slice(2).toUpperCase();
	}

	return fixed;
};

/** @param {import('eslint').Rule.RuleContext} context */
const create = () => ({
	Literal: node => {
		const {raw} = node;

		let fixed = raw;
		if (isNumber(node)) {
			fixed = fix(raw);
		} else if (isBigInt(node)) {
			fixed = fix(raw.slice(0, -1)) + 'n';
		}

		if (raw !== fixed) {
			return {
				node,
				messageId: MESSAGE_ID,
				fix: fixer => fixer.replaceText(node, fixed),
			};
		}
	},
});

/** @type {import('eslint').Rule.RuleModule} */
module.exports = {
	create: checkVueTemplate(create),
	meta: {
		type: 'suggestion',
		docs: {
			description: 'Enforce proper case for numeric literals.',
		},
		fixable: 'code',
		messages,
	},
};