Benchmark: JavaScript spread operator vs Object.assign performance immutable

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 Object.assign no mutation
const firstObject = { sampleData: 'Hello world' } const secondObject = { moreData: 'foo bar' } const finalObject = Object.assign({}, firstObject, secondObject);

Rendered benchmark preparation results:

Previous results

Test case name	Result
Using the spread operator
Using Object.assign
Using Object.assign no mutation

ⓘ Get performance results from real users on your website with Request Metrics.

Latest run results:

Run details: (Test run date: 4 months ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36

Browser/OS: Chrome 120 on Linux

Test name	Executions per second
Using the spread operator	38545340.0 Ops/sec
Using Object.assign	10769090.0 Ops/sec
Using Object.assign no mutation	8661344.0 Ops/sec

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