Array.indexOf vs Object's "in operator

JavaScript performance comparison

Revision 8 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',
       'test',
       'here',
    ]
   
    var obj = {
       'that' : null,
       'is' : null,
       'some' : null,
       'nice' : null,
       'test' : null,
       'here' : null
    }
};
</script>

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Testing in unknown unknown
Test Ops/sec
Array - Find first element
if (arr.indexOf('that') !== -1) {
  // found
}
pending…
Object - Find first element
if ('that' in obj) {
  // found
}
pending…
Array - Find last element
if (arr.indexOf('here') !== -1) {
  // found
}
pending…
Object - Find last element
if ('here' in obj) {
  // found
}
pending…
Object - Find first element (typeof)
if (typeof obj['that'] !== "undefined") {
  // found
}
pending…
Object - Find last element (typeof)
if (typeof obj['here'] !== "undefined") {
  // found
}
pending…
hasOwnProperty
if (obj.hasOwnProperty('here')){
  // found
}
pending…

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