object.keys vs for in (v18)

Revision 18 of this benchmark created by Some Dude on

Setup

var obj = {
      a: 0,
      b: 1,
      c: 2,
      d: 3,
      e: 4,
      f: 5,
      g: 6,
      h: 7,
      i: 8,
      j: 9
    };
    var sum = 0;
    var obj2 = Object.create(null);
    Object.keys(obj).forEach(function(k) {obj2[k] = obj[k];});

Teardown


    console.log(sum);

Test runner

Ready to run.

Testing in
TestOps/sec
1
var keys = Object.keys(obj);
for (var i = 0; i < keys.length; i++) {
  sum += obj[keys[i]];
}
ready
2
for (var key in obj) {
  if (obj.hasOwnProperty(key)) {
    sum += obj[key];
  }
}
ready
3
var keys = Object.keys(obj2);
for (var i = 0; i < keys.length; i++) {
  sum += obj2[keys[i]];
}
ready
4
for (var key in obj2) {
    sum += obj[key];
}
ready
5
for (var key in obj) {
    sum += obj[key];
}
ready

Revisions

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