Run results for: Object.assign vs spread vs _.extend

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 15_6 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) CriOS/104.0.5112.99 Mobile/15E148 Safari/604.1

Browser: Chrome Mobile iOS 104

Operating system: iOS 15.6

Device Platform: Mobile

Date tested: one year ago

Test name	Executions per second
Object.assign	3008917.0 Ops/sec
spread operator	6386942.0 Ops/sec
_.extend	3578284.0 Ops/sec

HTML Preparation code:

<script src="https://underscorejs.org/underscore-min.js"></script>

Tests:

Object.assign
var params = { b:"hello", c: true, d:7 }; var other = Object.assign({ a: 2 }, params);
spread operator
var params = { b:"hello", c: true, d:7 }; var other = { a: 2, ...params };
_.extend
var params = { b:"hello", c: true, d:7 }; var other = _.extend({ a: 2 }, params);

Run results for: Object.assign vs spread vs _.extend

Object.assign

spread operator

_.extend