Run results for: Spread operator vs mutation vs Object.assign with reduce

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/129.0.0.0 Safari/537.36

Browser: Chrome 129

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

with mutation

6.2M/s

with spread operator

1.7M/s

with object assign

356K/s

View exact numbers

Script Preparation code:

var range = (from, to) => {
  const output = []
  for(var x = from; x < to; x++){
    output.push(x)
  }
  return output
}

Tests:

with spread operator
range(0, 10).reduce((acc, num) => { return { ...acc, [num]: num } }, {})
with mutation
range(0, 10).reduce((acc, num) => { acc[num] = num return acc }, {})
with object assign
range(0, 10).reduce((acc, num) => { return Object.assign(acc, {[num]: num}) }, {})