site/node_modules/estree-util-is-identifier-name/lib/index.js
2024-10-14 08:09:33 +02:00

62 lines
1.8 KiB
JavaScript

/**
* @typedef Options
* Configuration.
* @property {boolean | null | undefined} [jsx=false]
* Support JSX identifiers (default: `false`).
*/
const startRe = /[$_\p{ID_Start}]/u
const contRe = /[$_\u{200C}\u{200D}\p{ID_Continue}]/u
const contReJsx = /[-$_\u{200C}\u{200D}\p{ID_Continue}]/u
const nameRe = /^[$_\p{ID_Start}][$_\u{200C}\u{200D}\p{ID_Continue}]*$/u
const nameReJsx = /^[$_\p{ID_Start}][-$_\u{200C}\u{200D}\p{ID_Continue}]*$/u
/** @type {Options} */
const emptyOptions = {}
/**
* Checks if the given code point can start an identifier.
*
* @param {number | undefined} code
* Code point to check.
* @returns {boolean}
* Whether `code` can start an identifier.
*/
// Note: `undefined` is supported so you can pass the result from `''.codePointAt`.
export function start(code) {
return code ? startRe.test(String.fromCodePoint(code)) : false
}
/**
* Checks if the given code point can continue an identifier.
*
* @param {number | undefined} code
* Code point to check.
* @param {Options | null | undefined} [options]
* Configuration (optional).
* @returns {boolean}
* Whether `code` can continue an identifier.
*/
// Note: `undefined` is supported so you can pass the result from `''.codePointAt`.
export function cont(code, options) {
const settings = options || emptyOptions
const re = settings.jsx ? contReJsx : contRe
return code ? re.test(String.fromCodePoint(code)) : false
}
/**
* Checks if the given value is a valid identifier name.
*
* @param {string} name
* Identifier to check.
* @param {Options | null | undefined} [options]
* Configuration (optional).
* @returns {boolean}
* Whether `name` can be an identifier.
*/
export function name(name, options) {
const settings = options || emptyOptions
const re = settings.jsx ? nameReJsx : nameRe
return re.test(name)
}