Run results for: .concat vs spread vs push inside reduce

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/16.5 Safari/605.1.15

Browser: Safari 16

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Script Preparation code:

var source = Array(100).fill(0).map((_, i) => Array(i).fill(1).map((_, i) => i))

Tests:

Array.prototype.concat
var result = source.reduce((acc, val) => { acc = acc.concat(val) return acc }, [])
Spread operator
var result = source.reduce((acc, val) => { return [...acc, ...val] }, [])
Array.prototype.push
var result = source.reduce((acc, val) => { acc.push(...val) return acc }, [])