Array.indexOf vs Object's "in operator

JavaScript performance comparison

Revision 6 of this test case created

Info

Testing if access through Array.indexOf or Object's in Operator is faster.

Preparation code

 
<script>
Benchmark.prototype.setup = function() {
    var arr = ['that', 'is', 'some', 'nice', 'some', 'test', 'here', ]
   
    var obj = {
      'that': null,
      'is': null,
      'some': null,
      'nice': null,
      'test': null,
      'here': null
    }
};
</script>

Test runner

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Testing in unknown unknown
Test Ops/sec
Array - Find first element
if (arr.indexOf('that') !== -1) {
  // found
}
pending…
Array - Find first element w/obj
if (typeof obj['that'] !== "undefined") {
  if (arr.indexOf('that') !== -1) {
    // found
  }
}
pending…
Array - Find none element
if (arr.indexOf('abcd') !== -1) {
  // found
}
pending…
Array - Find none element w/obj
if (typeof obj['abcd'] !== "undefined") {
  if (arr.indexOf('abcd') !== -1) {
    // found
  }
}
pending…
Array - Find first element (? and:)
arr['that'] 
?
//found
''
:
''
 
pending…
Array - Find first element (if statement)
if(arr['that']){

}
pending…

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