Web API Polyfills

ChildNode.js

// Modified from https://developer.mozilla.org/en-US/docs/Web/API/ChildNode/remove#Polyfill
[
    Element.prototype,
    CharacterData.prototype,
    DocumentType.prototype,
].forEach(function (proto) {
    if (!proto.hasOwnProperty('remove')) {
        Object.defineProperty(proto, 'remove', {
            configurable: true,
            enumerable: true,
            writable: true,
            value: function () {
                if (this.parentNode !== null) {
                    this.parentNode.removeChild(this);
                }
            },
        });
    }
});

Element.js

// Modified from https://developer.mozilla.org/en-US/docs/Web/API/Element/closest#Polyfill

/*
 * If browser supports a variation of matches(), (IE9+)
 * normalize to 'matches' on the prototype.
 */
if (!Element.prototype.matches) {
    Element.prototype.matches = Element.prototype.msMatchesSelector ||
                                Element.prototype.webkitMatchesSelector;
}

if (!Element.prototype.closest) {
    Element.prototype.closest = function (selectors) {
        var el = this;

        // fail fast if element isn't attached to the document
        if (!document.documentElement.contains(el)) {
            return null;
        }

        // Check if any ancestors match selectors
        while (el !== null && el.nodeType === 1) {
            if (el.matches(selectors)) {
                return el;
            } else {
                el = el.parentElement || el.parentNode;
            }
        }

        // Return null if no ancestors match
        return null;
    };
}

index.js

import './ChildNode.js'
import './Element.js'
import './Node.js'

Node.js

var proto = Node.prototype;
if (!proto.hasOwnProperty('isConnected')) {
    Object.defineProperty(proto, 'isConnected', {
        enumerable: true,
        get: function () {
            return (this.getRootNode().nodeType === Node.DOCUMENT_NODE);
        },
    });
}