eslint-plugin-unicorn-x/rules/prefer-string-raw.js

More than 100 powerful ESLint rules

import {isStringLiteral, isDirective} from './ast/index.js';
import {fixSpaceAroundKeyword} from './fix/index.js';

const MESSAGE_ID = 'prefer-string-raw';
const messages = {
	[MESSAGE_ID]: '`String.raw` should be used to avoid escaping `\\`.',
};

const BACKSLASH = '\\';

function unescapeBackslash(raw) {
	const quote = raw.charAt(0);

	return raw
		.slice(1, -1)
		.replaceAll(
			new RegExp(String.raw`\\(?<escapedCharacter>[\\${quote}])`, 'g'),
			'$<escapedCharacter>',
		);
}

/** @param {import('eslint').Rule.RuleContext} context */
const create = (context) => {
	context.on('Literal', (node) => {
		if (
			!isStringLiteral(node) ||
			isDirective(node.parent) ||
			((node.parent.type === 'ImportDeclaration' ||
				node.parent.type === 'ExportNamedDeclaration' ||
				node.parent.type === 'ExportAllDeclaration') &&
				node.parent.source === node) ||
			(node.parent.type === 'Property' &&
				!node.parent.computed &&
				node.parent.key === node) ||
			(node.parent.type === 'JSXAttribute' && node.parent.value === node) ||
			(node.parent.type === 'TSEnumMember' &&
				(node.parent.initializer === node || node.parent.id === node)) ||
			(node.parent.type === 'ImportAttribute' &&
				(node.parent.key === node || node.parent.value === node))
		) {
			return;
		}

		const {sourceCode} = context;
		const {raw} = node;
		if (
			raw.at(-2) === BACKSLASH ||
			!raw.includes(BACKSLASH + BACKSLASH) ||
			raw.includes('`') ||
			raw.includes('${') ||
			sourceCode.getLoc(node).start.line !== sourceCode.getLoc(node).end.line
		) {
			return;
		}

		const unescaped = unescapeBackslash(raw);
		if (unescaped !== node.value) {
			return;
		}

		return {
			node,
			messageId: MESSAGE_ID,
			*fix(fixer) {
				yield fixer.replaceText(node, `String.raw\`${unescaped}\``);
				yield* fixSpaceAroundKeyword(fixer, node, sourceCode);
			},
		};
	});
};

/** @type {import('eslint').Rule.RuleModule} */
const config = {
	create,
	meta: {
		type: 'suggestion',
		docs: {
			description: 'Prefer using the `String.raw` tag to avoid escaping `\\`.',
			recommended: true,
		},
		fixable: 'code',
		messages,
	},
};

export default config;