const polyfill = () => { if (!Array.prototype.at) { // Taken from https://github.com/tc39/proposal-relative-indexing-method#polyfill so that it works in tests /* eslint-disable */ Object.defineProperty(Array.prototype, "at", { value: function (n: number) { // ToInteger() abstract op n = Math.trunc(n) || 0; // Allow negative indexing from the end if (n < 0) { n += this.length; } // OOB access is guaranteed to return undefined if (n < 0 || n >= this.length) { return undefined; } // Otherwise, this is just normal property access return this[n]; }, writable: true, enumerable: false, configurable: true, }); } }; export default polyfill;