/** * @fileoverview A collection of methods for processing Espree's options. * @author Kai Cataldo */ //------------------------------------------------------------------------------ // Helpers //------------------------------------------------------------------------------ const SUPPORTED_VERSIONS = [ 3, 5, 6, 7, 8, 9, 10, 11, 12, 13 ]; /** * Get the latest ECMAScript version supported by Espree. * @returns {number} The latest ECMAScript version. */ export function getLatestEcmaVersion() { return SUPPORTED_VERSIONS[SUPPORTED_VERSIONS.length - 1]; } /** * Get the list of ECMAScript versions supported by Espree. * @returns {number[]} An array containing the supported ECMAScript versions. */ export function getSupportedEcmaVersions() { return [...SUPPORTED_VERSIONS]; } /** * Normalize ECMAScript version from the initial config * @param {(number|"latest")} ecmaVersion ECMAScript version from the initial config * @throws {Error} throws an error if the ecmaVersion is invalid. * @returns {number} normalized ECMAScript version */ function normalizeEcmaVersion(ecmaVersion = 5) { let version = ecmaVersion === "latest" ? getLatestEcmaVersion() : ecmaVersion; if (typeof version !== "number") { throw new Error(`ecmaVersion must be a number or "latest". Received value of type ${typeof ecmaVersion} instead.`); } // Calculate ECMAScript edition number from official year version starting with // ES2015, which corresponds with ES6 (or a difference of 2009). if (version >= 2015) { version -= 2009; } if (!SUPPORTED_VERSIONS.includes(version)) { throw new Error("Invalid ecmaVersion."); } return version; } /** * Normalize sourceType from the initial config * @param {string} sourceType to normalize * @throws {Error} throw an error if sourceType is invalid * @returns {string} normalized sourceType */ function normalizeSourceType(sourceType = "script") { if (sourceType === "script" || sourceType === "module") { return sourceType; } if (sourceType === "commonjs") { return "script"; } throw new Error("Invalid sourceType."); } /** * Normalize parserOptions * @param {Object} options the parser options to normalize * @throws {Error} throw an error if found invalid option. * @returns {Object} normalized options */ export function normalizeOptions(options) { const ecmaVersion = normalizeEcmaVersion(options.ecmaVersion); const sourceType = normalizeSourceType(options.sourceType); const ranges = options.range === true; const locations = options.loc === true; if (ecmaVersion !== 3 && options.allowReserved) { // a value of `false` is intentionally allowed here, so a shared config can overwrite it when needed throw new Error("`allowReserved` is only supported when ecmaVersion is 3"); } if (typeof options.allowReserved !== "undefined" && typeof options.allowReserved !== "boolean") { throw new Error("`allowReserved`, when present, must be `true` or `false`"); } const allowReserved = ecmaVersion === 3 ? (options.allowReserved || "never") : false; const ecmaFeatures = options.ecmaFeatures || {}; const allowReturnOutsideFunction = options.sourceType === "commonjs" || Boolean(ecmaFeatures.globalReturn); if (sourceType === "module" && ecmaVersion < 6) { throw new Error("sourceType 'module' is not supported when ecmaVersion < 2015. Consider adding `{ ecmaVersion: 2015 }` to the parser options."); } return Object.assign({}, options, { ecmaVersion, sourceType, ranges, locations, allowReserved, allowReturnOutsideFunction }); }