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

Run details:

User agent: Mozilla/5.0 (Linux; Android 12; SM-G9750) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/110.0.5481.192 Mobile Safari/537.36 OPR/74.1.3922.71199

Browser: Opera Mobile 74

Operating system: Android

Device Platform: Mobile

Date tested: one year ago

Test name	Executions per second
with spread operator	585994.1 Ops/sec
with mutation	2827563.5 Ops/sec
with object assign	97226.3 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