in operator vs hasOwnProperty vs undefined value for key

JavaScript performance comparison

Revision 2 of this test case created by Bry

Preparation code


      
      <script>
Benchmark.prototype.setup = function() {
  var testObj = {};
  var test_key = 9999;
  
  for ( var i = 0; i < 10000; i++ ){ testObj [ i ] = 1; };

};
</script>

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Testing in CCBot 2.0.0 / Other 0.0.0
Test Ops/sec
boolean
(testObj.test_key)
pending…
undefined value
( testObj [ test_key ] === undefined )
pending…
hasOwnProperty
( testObj.hasOwnProperty(test_key) )
pending…
in operator
( test_key in testObj )
pending…

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Revisions

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