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

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36

Browser: Chrome 114

Operating system: Windows

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 }, [])