polyfill of every array method in javascript [ES6]

everyPolyfill.js

Array.prototype.myEvery = function() {
    
    var arr = this;
    var len = arr.length;
    var fn = arguments[0];
    var thisArg = arguments[1];
   
 
    for (var i = 0; i < len; i++) {
        if(!fn.call(thisArg, arr[i], i, arr)) {
          return false;
        }
    }
    return true;

}

var arr = [1, 2, 3, 4, 5, 6, 7, 8];

var every = arr.every((item)=>item > 2);
var myEvery = arr.myEvery((item)=>item > 2);

console.log(every); // false
console.log(myEvery); // false