41 lines
1.3 KiB
TypeScript
41 lines
1.3 KiB
TypeScript
// 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(),
|
|
]);
|
|
}
|