Run results for: spread vs mutation vs Object.assign vs Object.assign (new) for reduce callback 1000

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/96.0.4664.110 Safari/537.36

Browser: Chrome 96

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 2 years ago

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, 1000).reduce((acc, num) => { return { ...acc, [num]: num } }, {})
with mutation
range(0, 1000).reduce((acc, num) => { acc[num] = num return acc }, {})
with object assign
range(0, 1000).reduce((acc, num) => { return Object.assign(acc, {[num]: num}) }, {})
with new object assign
range(0, 1000).reduce((acc, num) => { return Object.assign({}, acc, {[num]: num}) }, {})
foreach
const output = {}; range(0, 1000).forEach((num) => { output[num] = num; });