Test case details

Preparation Code

var arr = Array.from({length: 1000}, (_, i) => { return { 'test': i } })

Test cases

Test #1

var mf = arr.map(function(el) { if (el.test === 40) { return el.test } }).filter(function(v) { return v })

Test #2

var fm = arr.filter(function(el) { if (el.test === 40) { return el.test } }).map(function(v) { if (v) return v })

Test #3

var a = [] var mf = arr.forEach(function(el) { if (el.test === 40) { return a.push(el.test) } })