Run results for: JavaScript spread operator vs Object.assign performance 2123

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/95.0.4638.54 Safari/537.36

Browser: Chrome 95

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
Using the spread operator	312106.8 Ops/sec
Using Object.assign	2090198.0 Ops/sec
Empty object assign	1289994.0 Ops/sec

Script Preparation code:

var firstObject = { sampleData: 'Hello world', sampleData2: 'Hello world', sampleData3: 'Hello world',sampleData4: 'Hello world' };
var secondObject = { moreData: 'foo bar',moreData2: 'foo bar',moreData3: 'foo bar',moreData4: 'foo bar' };

Tests:

Using the spread operator
const finalObject = { ...firstObject, ...secondObject };
Using Object.assign
const finalObject = Object.assign(firstObject, secondObject);
Empty object assign
const finalObject = Object.assign({}, firstObject, secondObject);

Run results for: JavaScript spread operator vs Object.assign performance 2123

Using the spread operator

Using Object.assign

Empty object assign