Run results for: Lodash cloneDeep vs deepFreeze vs deepClone vs JSON.parse(JSON.stringify())

Test name	Executions per second
✓ custom deepClone()	1,375,764 Ops/sec
custom deepFreeze()	453,924 Ops/sec
JSON	420,146 Ops/sec
Lodash cloneDeep	137,307 Ops/sec

Test name

Executions per second

✓ custom deepClone()

1,375,764 Ops/sec

custom deepFreeze()

453,924 Ops/sec

JSON

420,146 Ops/sec

Lodash cloneDeep

137,307 Ops/sec

Script Preparation code:

var MyObject = {
  description: 'Creates a deep copy of source, which should be an object or an array.',
  myNumber: 123456789,
  myBoolean: true,
  array: [1,2,3,4,5,6,7,8,9,0],
  nestedObject: {
  	a: [{x: 1}, {x: 1}, {x: 1}],
    b: [{x: 1}, {x: 1}, {x: 1}],
    c: [{x: 1}, {x: 1}, {x: 1}]
  },
  jayson: {
    stringify: 'JSON.stringify() method converts a JavaScript value to a JSON string....',
    parse: 'JSON.parse() method parses a JSON string...'
  }
};

var myCopy = null;

function deepFreeze(x) {

  if (!x || typeof x !== 'object') {
  	return x;
  }
  
  if (Array.isArray(x)) {
  	const y = [];
    for (let i = 0; i < x.length; i++) {
      y.push(deepFreeze(x[i]));
    }
    return Object.freeze(y);
  }
  
  const y = {};
  
  for (const key in x) {
  	if (x.hasOwnProperty(key)) {
      y[key] = deepFreeze(x[key]);
    }
  }
  
  return Object.freeze(y);
  
}

function deepClone(x) {

  if (!x || typeof x !== 'object') {
    return x;
  }

  if (Array.isArray(x)) {
    const y = [];
    for (let i = 0; i < x.length; i++) {
      y.push(deepClone(x[i]));
    }
    return y;
  }

  const y = {};
  for (const key in x) {
  	if (x.hasOwnProperty(key)) {
      y[key] = deepClone(x[key]);   
    }
  }

  return y;

}