Run results for: spread vs mutation vs Object.assign for reduce callback

Run details:

User agent: Mozilla/5.0 (Linux; Android 13; SAMSUNG SM-S916B) AppleWebKit/537.36 (KHTML, like Gecko) SamsungBrowser/23.0 Chrome/115.0.0.0 Mobile Safari/537.36

Browser: Chrome Mobile 115

Operating system: Android

Device Platform: Mobile

Date tested: 10 months ago

Test name	Executions per second
with spread operator	1049150.0 Ops/sec
with mutation	4454869.0 Ops/sec
with object assign	177521.5 Ops/sec

Tests:

with spread operator
const range = (from, to) => { const output = [] for(var x = from; x < to; x++){ output.push(x) } return output } range(0, 10).reduce((acc, num) => { return { ...acc, [num]: num } }, {})
with mutation
const range = (from, to) => { const output = [] for(var x = from; x < to; x++){ output.push(x) } return output } range(0, 10).reduce((acc, num) => { acc[num] = num return acc }, {})
with object assign
const range = (from, to) => { const output = [] for(var x = from; x < to; x++){ output.push(x) } return output } range(0, 10).reduce((acc, num) => { return Object.assign(acc, {[num]: num}) }, {})

Run results for: spread vs mutation vs Object.assign for reduce callback

with spread operator

with mutation

with object assign