42 lines
		
	
	
	
		
			1.5 KiB
		
	
	
	
		
			TypeScript
		
	
	
	
	
	
			
		
		
	
	
			42 lines
		
	
	
	
		
			1.5 KiB
		
	
	
	
		
			TypeScript
		
	
	
	
	
	
| // Convenience function to load polyfills and return a promise when it's done.
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| // If there are no polyfills, then this is just Promise.resolve() which means
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| // it will execute in the same tick of the event loop (i.e. near-instant).
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| 
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| import { loadIntlPolyfills } from './intl';
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| 
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| function importBasePolyfills() {
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|   return import(/* webpackChunkName: "base_polyfills" */ './base_polyfills');
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| }
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| 
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| function importExtraPolyfills() {
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|   return import(/* webpackChunkName: "extra_polyfills" */ './extra_polyfills');
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| }
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| 
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| export function loadPolyfills() {
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|   const needsBasePolyfills = !(
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|     'toBlob' in HTMLCanvasElement.prototype &&
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|     'assign' in Object &&
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|     'values' in Object &&
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|     'Symbol' in window &&
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|     'finally' in Promise.prototype
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|   );
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| 
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|   // Latest version of Firefox and Safari do not have IntersectionObserver.
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|   // Edge does not have requestIdleCallback.
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|   // This avoids shipping them all the polyfills.
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|   /* eslint-disable @typescript-eslint/no-unnecessary-condition -- those properties might not exist in old browsers, even if they are always here in types */
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|   const needsExtraPolyfills = !(
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|     window.AbortController &&
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|     window.IntersectionObserver &&
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|     window.IntersectionObserverEntry &&
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|     'isIntersecting' in IntersectionObserverEntry.prototype &&
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|     window.requestIdleCallback
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|   );
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|   /* eslint-enable @typescript-eslint/no-unnecessary-condition */
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| 
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|   return Promise.all([
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|     loadIntlPolyfills(),
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|     needsBasePolyfills && importBasePolyfills(),
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|     needsExtraPolyfills && importExtraPolyfills(),
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|   ]);
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| }
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