pinafore/src/routes/_utils/polyfills/loadPolyfills.js

import {
  importIntlListFormat,
  importIntlLocale, importIntlPluralRules, importIntlRelativeTimeFormat,
  importRequestIdleCallback
} from './asyncPolyfills'

async function loadIntlPolyfillsIfNecessary () {
  // Have to chain these so that they load in the proper order.
  // Luckily these requests aren't done in serial, because we're using the same Webpack
  // chunk name for each one.
  if (typeof Intl.Locale !== 'function') {
    await importIntlLocale()
  }
  if (typeof Intl.PluralRules !== 'function') {
    await importIntlPluralRules()
  }
  await Promise.all([
    typeof Intl.RelativeTimeFormat !== 'function' && importIntlRelativeTimeFormat(),
    typeof Intl.ListFormat !== 'function' && importIntlListFormat()
  ])
}

export function loadPolyfills () {
  return Promise.all([
    typeof requestIdleCallback !== 'function' && importRequestIdleCallback(),
    loadIntlPolyfillsIfNecessary()
  ])
}