Run results for: JavaScript spread operator vs Object.assign vs different spread performance v2

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/16.3 Safari/605.1.15

Browser: Safari 16

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
Using the spread operator with constant inside	20825816.0 Ops/sec
Using Object.assign to merge two objects	11579456.0 Ops/sec
Using the spread operator to merge two objects	10942229.0 Ops/sec
Using the spread operator with two extra variables	21341744.0 Ops/sec
Composing objects into new one	476012416.0 Ops/sec

Tests:

Using the spread operator with constant inside
const firstObject = { sampleData: 'Hello world' } const secondObject = { moreData: 'foo bar' } const finalObject = { ...secondObject, __key: "a key", __src: "a src", };
Using Object.assign to merge two objects
const firstObject = { __key: "a key", __src: "a src", } const secondObject = { moreData: 'foo bar' } const finalObject = Object.assign(firstObject, secondObject);
Using the spread operator to merge two objects
const firstObject = { __key: "a key", __src: "a src", } const secondObject = { moreData: 'foo bar' } const finalObject = { ...secondObject, ...firstObject };
Using the spread operator with two extra variables
const __key = "a key"; const __src = "a src"; const secondObject = { moreData: 'foo bar' } const finalObject = { ...secondObject, __key, __src, };
Composing objects into new one
const __key = "a key"; const __src = "a src"; const data = { moreData: 'foo bar' } const finalObject = { data, __key, __src, };