Method constructor

packages/intl-locale/index.ts:448–592

(tag: string | Locale, opts?: IntlLocaleOptions)

export class Locale {
  constructor(tag: string | Locale, opts?: IntlLocaleOptions) {
    // test262/test/intl402/RelativeTimeFormat/constructor/constructor/newtarget-undefined.js
    // Cannot use `new.target` bc of IE11 & TS transpiles it to something else
    const newTarget = this && this instanceof Locale ? this.constructor : void 0
    if (!newTarget) {
      throw new TypeError("Intl.Locale must be called with 'new'")
    }

    const {relevantExtensionKeys} = Locale

    const internalSlotsList: Array<keyof IntlLocaleInternal> = [
      'initializedLocale',
      'locale',
      'calendar',
      'collation',
      'hourCycle',
      'numberingSystem',
    ]

    if (relevantExtensionKeys.indexOf('kf') > -1) {
      internalSlotsList.push('caseFirst')
    }

    if (relevantExtensionKeys.indexOf('kn') > -1) {
      internalSlotsList.push('numeric')
    }

    if (tag === undefined) {
      throw new TypeError(
        "First argument to Intl.Locale constructor can't be empty or missing"
      )
    }

    if (typeof tag !== 'string' && typeof tag !== 'object') {
      throw new TypeError('tag must be a string or object')
    }

    let tagInternalSlots
    if (
      typeof tag === 'object' &&
      (tagInternalSlots = getInternalSlots(tag)) &&
      HasOwnProperty(tagInternalSlots, 'initializedLocale')
    ) {
      tag = tagInternalSlots.locale
    } else {
      tag = tag.toString() as string
    }

    let internalSlots = getInternalSlots(this, internalSlotsList)

    let options = CoerceOptionsToObject<IntlLocaleOptions>(opts)

    tag = applyOptionsToTag(tag, options)
    const opt = Object.create(null)
    const calendar = GetOption(
      options,
      'calendar',
      'string',