simple ponyfills

elementClosest.d.ts

/**
 * Element.closest ponyfill
 */
export function elementClosest(element: Element, selector: string): Element | null

elementClosest.js

export const elementClosest = (() => {
  const proto = typeof window === "undefined" ? {} : window.Element.prototype;
  const match =
    proto.matches || proto.msMatchesSelector || proto.webkitMatchesSelector;
  return proto.closest
    ? (el, css) => el.closest(css)
    : (el, css) => {
        // IE jumps to shadow SVG DOM on clicking an SVG defined by <use>.
        // If so, jump back to <use> element and traverse real DOM
        if (el.correspondingUseElement) el = el.correspondingUseElement;
        for (; el; el = el.parentElement) if (match.call(el, css)) return el;
        return null;
      };
})();

objectEntries.d.ts

/**
 * Object.entries ponyfill
 */
export function objectEntries<T>(o: { [s: string]: T } | ArrayLike<T>): [string, T][]
export function objectEntries(o: {}): [string, any][];

objectEntries.js

export const objectEntries = Object.entries || ((obj) => {
  const ownProps = Object.keys(obj);
  let i = ownProps.length;
  const resArray = new Array(i); // preallocate the Array
  while (i--) resArray[i] = [ownProps[i], obj[ownProps[i]]];
  return resArray;
});

objectFromEntries.d.ts

/**
 * Object.fromEntries ponyfill
 */
export function ObjectFromEntries<T = any>(entries: Iterable<readonly [PropertyKey, T]>): { [k in PropertyKey]: T }; 
export function ObjectFromEntries(entries: Iterable<readonly any[]>): any;

objectFromEntries.js

export const objectFromEntries =
  Object.fromEntries ||
  (iterable =>
    [...iterable].reduce((obj, [key, val]) => {
      obj[key] = val;
      return obj;
    }, {}));