Benchmark: JavaScript Object Mutation vs Object.assign performance

Tests:

Using Mutation
const baseObject = { } baseObject.sampleData = 'Hello world'; baseObject.moreData = 'foo bar'; const resultObject = baseObject;
Using Object.assign
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 Mutation
Using Object.assign

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Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/105.0.0.0 Safari/537.36

Browser/OS: Chrome 105 on Mac OS X 10.15.7

Test name	Executions per second
Using Mutation	987085000.0 Ops/sec
Using Object.assign	11378500.0 Ops/sec

JavaScript Object Mutation vs Object.assign performance (version: 0)