Run results for: Object assignment performance

Run details:

User agent: Mozilla/5.0 (Linux; Android 8.1.0; Redmi Note 5 Build/OPM1.171019.011; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/68.0.3440.91 Mobile Safari/537.36 Juejin/225

Browser: Chrome Mobile 68

Operating system: Android 8.1.0

Device Platform: Mobile

Date tested: 4 years ago

Test name	Executions per second
Using the spread operator	939737.6 Ops/sec
Using Object.assign	1232274.0 Ops/sec
Using lodash.assign	651301.2 Ops/sec
Using for...in	11953610.0 Ops/sec

HTML Preparation code:

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

Tests:

Using the spread operator
const firstObject = { sampleData: 'Hello world' } const secondObject = { moreData: 'foo bar' } const finalObject = { ...firstObject, ...secondObject };
Using Object.assign
const firstObject = { sampleData: 'Hello world' } const secondObject = { moreData: 'foo bar' } const finalObject = Object.assign(firstObject, secondObject);
Using lodash.assign
const firstObject = { sampleData: 'Hello world' } const secondObject = { moreData: 'foo bar' } const finalObject = _.assign(firstObject, secondObject);
Using for...in
function assign(target, source) { for (let prop in source) { target[prop] = source[prop]; } return target; } const firstObject = { sampleData: 'Hello world' } const secondObject = { moreData: 'foo bar' } const finalObject = assign(firstObject, secondObject);

Run results for: Object assignment performance

Using the spread operator

Using Object.assign

Using lodash.assign

Using for...in