Benchmark: spread vs mutation vs Object.assign vs Object.assign (new) for reduce callback

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}) }, {})
with new object assign
range(0, 10).reduce((acc, num) => { return Object.assign({}, acc, {[num]: num}) }, {})
foreach
const output = {}; range(0, 10).forEach((num) => { output[num] = num; });

Rendered benchmark preparation results:

Previous results

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Latest run results:

Run details: (Test run date: 2 years ago)

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spread vs mutation vs Object.assign vs Object.assign (new) for reduce callback (version: 2)