Run results for: flatMap() vs filter().map() vs foreach and push

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:135.0) Gecko/20100101 Firefox/135.0

Browser: Firefox 135

Operating system: Mac OS X 10.15

Device Platform: Desktop

Date tested: one year ago

foreach & push

1K/s

filter().map()

772/s

flatMap()

692/s

View exact numbers

Script Preparation code:

var arr = [];
var i = 0;

while (i <= 1E5) arr[i] = i++;

Tests:

filter().map()
var result = arr.filter(x => x % 3).map(x => x/100)
flatMap()
var result = arr.flatMap(x => x % 3 ? x/100 : [])
foreach & push
var result = []; arr.forEach(x => { if (x%3) { result.push(x/100) } })