Benchmark: JavaScript spread vs Object.assign performance vs native spread

Tests:

Using the spread operator
"use strict"; function ownKeys(object, enumerableOnly) { var keys = Object.keys(object); if (Object.getOwnPropertySymbols) { var symbols = Object.getOwnPropertySymbols(object); if (enumerableOnly) symbols = symbols.filter(function (sym) { return Object.getOwnPropertyDescriptor(object, sym).enumerable; }); keys.push.apply(keys, symbols); } return keys; } function _objectSpread(target) { for (var i = 1; i < arguments.length; i++) { var source = arguments[i] != null ? arguments[i] : {}; if (i % 2) { ownKeys(Object(source), true).forEach(function (key) { _defineProperty(target, key, source[key]); }); } else if (Object.getOwnPropertyDescriptors) { Object.defineProperties(target, Object.getOwnPropertyDescriptors(source)); } else { ownKeys(Object(source)).forEach(function (key) { Object.defineProperty(target, key, Object.getOwnPropertyDescriptor(source, key)); }); } } return target; } function _defineProperty(obj, key, value) { if (key in obj) { Object.defineProperty(obj, key, { value: value, enumerable: true, configurable: true, writable: true }); } else { obj[key] = value; } return obj; } var firstObject = { sampleData: 'Hello world' }; var secondObject = { moreData: 'foo bar' }; var finalObject = _objectSpread(_objectSpread({}, firstObject), secondObject);
Using Object.assign
const firstObject = { sampleData: 'Hello world' } const secondObject = { moreData: 'foo bar' } const finalObject = Object.assign({}, firstObject, secondObject);
use...
const firstObject = { sampleData: 'Hello world' } const secondObject = { moreData: 'foo bar' } const finalObject = {...firstObject, ...secondObject}

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Using the spread operator
Using Object.assign
use...

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: one month ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.0.0 Safari/537.36

Browser/OS: Chrome 122 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Using the spread operator	711281.1 Ops/sec
Using Object.assign	5268026.0 Ops/sec
use...	20779810.0 Ops/sec

JavaScript spread vs Object.assign performance vs native spread (version: 0)

Comparing performance of: Using the spread operator vs Using Object.assign vs use...

Created: 2 years ago by: Guest

Jump to the latest result

Using the spread operator

Using Object.assign

use...

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A