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// Convenience function to load polyfills and return a promise when it's done.
// If there are no polyfills, then this is just Promise.resolve() which means
// it will execute in the same tick of the event loop (i.e. near-instant).
import { loadIntlPolyfills } from './intl';
function importBasePolyfills() {
return import(/* webpackChunkName: "base_polyfills" */ './base_polyfills');
}
function importExtraPolyfills() {
return import(/* webpackChunkName: "extra_polyfills" */ './extra_polyfills');
}
export function loadPolyfills() {
const needsBasePolyfills = !(
'toBlob' in HTMLCanvasElement.prototype &&
'assign' in Object &&
'values' in Object &&
'Symbol' in window &&
'finally' in Promise.prototype
);
// Latest version of Firefox and Safari do not have IntersectionObserver.
// Edge does not have requestIdleCallback.
// This avoids shipping them all the polyfills.
const needsExtraPolyfills = !(
window.AbortController &&
window.IntersectionObserver &&
window.IntersectionObserverEntry &&
'isIntersecting' in IntersectionObserverEntry.prototype &&
window.requestIdleCallback
);
return Promise.all([
loadIntlPolyfills(),
needsBasePolyfills && importBasePolyfills(),
needsExtraPolyfills && importExtraPolyfills(),
]);
}