Benchmark: JavaScript spread operator vs Object.assign performance ( nested objects ) into empty object

Tests:

Using the spread operator
const firstObject = { sampleData: 'Hello world', nested: { nestedData: "Worlds" } } const secondObject = { moreData: 'foo bar', oneNest: { secondNest: { nestedData: "Hellos" }} } const finalObject = { ...firstObject, ...secondObject };
Using Object.assign into empty object
const firstObject = { sampleData: 'Hello world', nested: { nestedData: "Worlds" } } const secondObject = { moreData: 'foo bar', oneNest: { secondNest: { nestedData: "Hellos" }} } const finalObject = Object.assign({}, firstObject, secondObject);

Rendered benchmark preparation results:

Previous results

Test case name	Result
Using the spread operator
Using Object.assign into empty object

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Latest run results:

Run details: (Test run date: 15 days ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/123.0.0.0 Safari/537.36

Browser/OS: Chrome 123 on Mac OS X 10.15.7

Test name	Executions per second
Using the spread operator	21351390.0 Ops/sec
Using Object.assign into empty object	8350314.0 Ops/sec

JavaScript spread operator vs Object.assign performance ( nested objects ) into empty object (version: 0)