import raf from 'raf'; export function throttleByAnimationFrame(fn: (...args: any[]) => void) { let requestId: number | null; const later = (args: any[]) => () => { requestId = null; fn(...args); }; const throttled = (...args: any[]) => { if (requestId == null) { requestId = raf(later(args)); } }; (throttled as any).cancel = () => raf.cancel(requestId!); return throttled; } export function throttleByAnimationFrameDecorator() { return function throttle(target: any, key: string, descriptor: any) { const fn = descriptor.value; let definingProperty = false; return { configurable: true, get() { // In IE11 calling Object.defineProperty has a side-effect of evaluating the // getter for the property which is being replaced. This causes infinite // recursion and an "Out of stack space" error. // eslint-disable-next-line no-prototype-builtins if (definingProperty || this === target.prototype || this.hasOwnProperty(key)) { /* istanbul ignore next */ return fn; } const boundFn = throttleByAnimationFrame(fn.bind(this)); definingProperty = true; Object.defineProperty(this, key, { value: boundFn, configurable: true, writable: true, }); definingProperty = false; return boundFn; }, }; }; }