Run results for: Object cloning with Lodash clone vs ES6 object spread vs ES6 Object.assign vs Json copy

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36

Browser: Chrome 97

Operating system: Windows

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
Lodash clone	1595850.1 Ops/sec
ES6 spread	11437084.0 Ops/sec
ES6 Object.assign	3367141.8 Ops/sec
Json	439116.3 Ops/sec
copy	160056.5 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 o = {
 a: {
   b: 1,
   c: 2,
   d: 3,
   j: {
     k: [1,2,3],
     l: [4,5,6]
   },
 },
 e: [1,2,3,4,5,6],
 f: 1,
 g: {
   h: 1,
 }
}

var visited = Symbol('visited');
var stopProcessing = false;

function copy(object) {
    // dates
    if (object instanceof Date) {
        return new Date(object.getTime());
        // arrays
    } else if (object instanceof Array) {
        const target = [];

        for (const obj of object) {
            target.push(copy(obj));
        }

        return target;
        // objects
    } else if (object instanceof Object) {
        if (object[visited]) {
            delete object[visited];
            return object;
        }

        if (stopProcessing) {
            return object;
        }

        object[visited] = true;

        const target = {};

        for (const prop in object) {
            if (object.hasOwnProperty(prop)) {
                if (object[visited]) {
                    delete object[visited];
                    stopProcessing = true;
                }

                target[prop] = copy(object[prop]);
            }
        }

        stopProcessing = false;
        return target;
    } else {
        // it's a primitive
        return object;
    }
}

Tests:

Lodash clone
const a = _.clone(o)
ES6 spread
const a = { ...o }
ES6 Object.assign
const a = Object.assign({}, o)
Json
const a = JSON.parse(JSON.stringify(o))
copy
const a = copy(o);

Run results for: Object cloning with Lodash clone vs ES6 object spread vs ES6 Object.assign vs Json copy

Lodash clone

ES6 spread

ES6 Object.assign

Json

copy