Test case details

Preparation Code

<script> var ar = [];   for (var i = 0; i < 249; i++)  { ar[i] = 'asset!' + i;  } </script>
"use strict";         Array.prototype.indexOf2 = function (x) {     for (let i = 0; i < this.length; i++) {     if (this[i] === x) return i;     }     return -1;     };         Array.prototype.indexOf3 = function (x) {     var i = this.length;     while(i--) {       if(this[i] === key) return i;     }     return -1;     };

Test cases

Test #1

var key = ar[Math.floor(Math.random()*249)]; var a = ar.indexOf2(key);

Test #2

var key = ar[Math.floor(Math.random()*249)]; var a = ar.indexOf3(key);

Test #3

var key = ar[Math.floor(Math.random()*249)]; var a = ar.indexOf(key);