cloning an object

JavaScript performance comparison

Revision 54 of this test case created by

Preparation code

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>

      
<script>
Benchmark.prototype.setup = function() {
  var oldObject = {
    a: 1,
    b: 2,
    c: 3,
    d: 4,
    e: 5,
    f: function() {
      return 6;
    },
    g: [7, 8, 9]
  };
  
  var cloneDeep = function(obj) {
    // Handle string, int, boolean, null or undefined
    if (null == obj || "object" != typeof obj) {
      return obj;
    }
  
    var copy;
    // Handle Date
    if (obj instanceof Date) {
      copy = new Date();
      copy.setTime(obj.getTime());
      return copy;
    }
  
    // Handle Array
    if (obj instanceof Array) {
      copy = [];
      for (var i = 0, len = obj.length; i < len; i++) {
        copy[i] = cloneDeep(obj[i]);
      }
      return copy;
    }
  
    // Handle Object
    if (obj instanceof Object) {
      copy = {};
      for (var attr in obj) {
        if (obj.hasOwnProperty(attr)) {
          copy[attr] = cloneDeep(obj[attr]);
        }
      }
      return copy;
    }
  
    console.error("Unable to copy object! Its type isn't supported.", obj);
  }
  
    function clone(obj) {
      var target = {};
      for (var i in obj) {
        if (obj.hasOwnProperty(i)) {
          target[i] = obj[i];
        }
      }
      return target;
    }
  
  Object.defineProperties(Object, {
    'extend': {
      'configurable': true,
      'enumerable': false,
      'value': function extend(what, wit) {
        var extObj, witKeys = Object.keys(wit);
  
        extObj = Object.keys(what).length ? Object.clone(what) : {};
  
        witKeys.forEach(function(key) {
          Object.defineProperty(extObj, key, Object.getOwnPropertyDescriptor(wit, key));
        });
  
        return extObj;
      },
      'writable': true
    },
    'clone': {
      'configurable': true,
      'enumerable': false,
      'value': function clone(obj) {
        return Object.extend({}, obj);
      },
      'writable': true
    }
  });

};
</script>

Preparation code output

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Testing in CCBot 2.0.0 / Other 0.0.0
Test Ops/sec
jQuery.extend() deep
var newObject = jQuery.extend(true, {}, oldObject);
pending…
JSON stringify/parse
var newObject = JSON.parse(JSON.stringify(oldObject));
pending…
jQuery.extend()
var newObject = jQuery.extend({}, oldObject);
pending…
clone function
var newObject = clone(oldObject);
pending…
ES5 Object.clone
var newObject = Object.clone(oldObject);
pending…
stringify eval
var newObject = eval("(" + JSON.stringify(oldObject) + ")");
pending…
sharc cloneDeep
var newObject = cloneDeep(oldObject);
pending…

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Revisions

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