Nodejs Utililty Methods Array Add All

Array.prototype.addAll = function( list ) {
  for( var i=0; i<list.length; i++ ) {
    this.push( list[i] );
  return this;
};

Array.prototype.addAll = function(addingElements) {
  for (var elementIndex = 0; elementIndex < addingElements.length; ++elementIndex) {
    this.push(addingElements[elementIndex]);
};

Array.prototype.addAll = function (arr) {
    var len = arr.length;
    for (var i = 0; i < len; i++) {
        this.push(arr[i]);
};

"use strict";
Array.prototype.addAll = function (arr) {
    for (const elm of arr) {
        this.push(elm);
};
if (!Array.prototype.includes) {
    Array.prototype.includes = function (element) {
        return this.indexOf(element) > -1;
...

Array.prototype.addAll = function(index, elements) {
  if (arguments.length == 2) {
    var n = this.length, m = elements.length;
    this.length += m;
    for (var i = n - 1; i >= index; i--) {
      this[i + m] = this[i];
    for (var i = 0; i < m; i++) {
      this[i + index] = elements[i];
...

Array.prototype.addAll = function(index, items){
  if (items === undefined){
    items = index;
    index = 0;
  for (var i=0; i<items.length; i++){
    this.add(index+i, items[i]);
  return true;
...

Array.prototype.addAll = (items) => {
    this.push.apply(this, items);
    this.push(null);
    this.pop();