Run results for: Lodash cloneDeep vs best native cloneDeep option

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.122 Safari/537.36

Browser: Chrome 80

Operating system: Linux

Device Platform: Desktop

Date tested: 4 years ago

Test name	Executions per second
Lodash cloneDeep	137389.4 Ops/sec
Native map deep slice(turns objects into arrays)	2343007.8 Ops/sec
Native JSON parse	168998.5 Ops/sec
Native map deep slice at 0(turns objects into arrays)	2380827.2 Ops/sec
Native map(shallow clone)	4522384.5 Ops/sec
Recursive deep clone	159019.0 Ops/sec
Map deep clone	174013.3 Ops/sec
Object.assign shallow clone	1582349.1 Ops/sec
Native Map with clone function (Deep)	170952.2 Ops/sec

HTML Preparation code:


<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Script Preparation code:

var testArray = [{
  description: 'Random description.',
  testNumber: 123456789,
  testBoolean: true,
  testObject: {
    testString: 'test string',
    testNumber: 12345
  },
  testArray: [{
    myName: 'test name',
    myNumber: 123245
  }]
},{
  description: 'Random description.',
  testNumber: 123456789,
  testBoolean: true,
  testObject: {
    testString: 'test string',
    testNumber: 12345
  },
  testArray: [{
    myName: 'test name',
    myNumber: 123245
  }]
}];

var testCopy = null;

var deepClone = function(obj) {
   var out;
    if (Array.isArray(obj)) {
        out = [];
        for (var index = 0; index < obj.length; ++index) {
            let subArray = obj[index];
            out.push((subArray === null) ? subArray : (subArray instanceof Date) ? new Date(subArray.valueOf()) : (typeof subArray === 'object') ? deepClone(subArray) : subArray);
        }
    } else {
        out = {};
        for (var key in obj) {
            var subObject = obj[key];
            out[key] = subObject === null ? subObject : subObject instanceof Date ? new Date(subObject.valueOf()) : (typeof subObject === 'object') ? deepClone(subObject) : subObject;
            
           
        }
    }
    return out;
};


function clone(obj) {
    var copy;

    // Handle the 3 simple types, and null or undefined
    if (null == obj || "object" != typeof obj) return obj;

    // 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] = clone(obj[i]);
        }
        return copy;
    }

    // Handle Object
    if (obj instanceof Object) {
        copy = {};
        for (var attr in obj) {
            if (obj.hasOwnProperty(attr)) copy[attr] = clone(obj[attr]);
        }
        return copy;
    }

    throw new Error("Unable to copy obj! Its type isn't supported.");
}

Tests:

Lodash cloneDeep
testCopy = _.cloneDeep(testArray);
Native map deep slice(turns objects into arrays)
testCopy = testArray.map(arr => testArray.slice());
Native JSON parse
testCopy = JSON.parse(JSON.stringify(testArray));
Native map deep slice at 0(turns objects into arrays)
testCopy = testArray.map(arr => testArray.slice(0));
Native map(shallow clone)
testCopy = testArray.map(arr => arr);
Recursive deep clone
testCopy = deepClone(testArray);
Map deep clone
testCopy = testArray.map(arr => deepClone(arr));
Object.assign shallow clone
testCopy = Object.assign([...testArray]);
Native Map with clone function (Deep)
testCopy = testArray.map(item => clone(item));

Run results for: Lodash cloneDeep vs best native cloneDeep option

compare array copy/clone methods

Lodash cloneDeep

Native map deep slice(turns objects into arrays)

Native JSON parse

Native map deep slice at 0(turns objects into arrays)

Native map(shallow clone)

Recursive deep clone

Map deep clone

Object.assign shallow clone

Native Map with clone function (Deep)