Run results for: Array loop vs foreach vs map for update field in object

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/136.0.0.0 Safari/537.36 Edg/136.0.0.0

Browser: Chrome 136

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Benchmark engine: Benchmark.js

foreach

698K/s

map

473K/s

for

363K/s

View exact numbers

Test name	Executions per second
✓ foreach	697,642 Ops/sec
map	473,208 Ops/sec
for	363,042 Ops/sec

Script Preparation code:

   var arr = [];
   for (var i = 0; i < 1000; i++) {
       arr[i] = {
           'id': i
       };
   }

   function someFn(i) {
       return i * 3 * 8;
   }

Tests:

foreach
arr.forEach(function (item){ item.data = someFn(item.id); })
for
for (var i = 0, len = arr.length; i < len; i++) { arr[i].data = someFn(arr[i].id); }
map
arr.map(function(item){ item.data=someFn(item.id); return item; });