Run results for: JavaScript spread operator vs Object.assign performance reassign same variable

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:122.0) Gecko/20100101 Firefox/122.0

Browser: Firefox 122

Operating system: Mac OS X 10.15

Device Platform: Desktop

Date tested: 2 years ago

Benchmark engine: Benchmark.js

Using Object.assign

16.6M/s

Using the spread operator

5.8M/s

View exact numbers

Test name	Executions per second
✓ Using Object.assign	16,576,126 Ops/sec
Using the spread operator	5,761,224 Ops/sec

Tests:

Using the spread operator
let firstObject = { sampleData: 'Hello world' } const secondObject = { moreData: 'foo bar' } firstObject = {...firstObject, ...secondObject}
Using Object.assign
const firstObject = { sampleData: 'Hello world' } const secondObject = { moreData: 'foo bar' } Object.assign(firstObject, secondObject);