var elementToCheck = 500;
    var ar = [];
    var arrayLength = 1000;
    while( arrayLength-- >= 0) {
       ar.push(arrayLength);
       
    }
    function fastIndexOf(arr, search) {
      for(var i = 0; i < arr.length; i++) {
        if(arr[i] === search) {
          return i;
        }
      }
    
      return -1;
    }

Teardown JS

Test cases

Test #1

Title *

Async

Code *

var a = undefined;

for (var i = 0, l = ar.length; i < l; i++) {
 if (i in ar && ar[i] === elementToCheck) {
   a = i;
   break;
 }
}

Test #2

Title *

Async

Code *var a = ar.indexOf(elementToCheck);

Test #3

Title *

Async

Code *

// NOTE: This searches back to front
var it = ar.length;
while (--it) {
  if (ar[it] === elementToCheck) {
    break;
  }
}

Test #4

Title *

Async

Code *

for(var i = 0; i < ar.length; i++) {
  if(ar[i] === elementToCheck) {
    break;
  }
}

Test #5

Title *

Async

Code *var a = fastIndexOf(ar, elementToCheck);

Test case details

Preparation Code

Test cases

Test #1

Test #2

Test #3

Test #4

Test #5