Run results for: getOwnPropertyNames vs Object.keys

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:81.0) Gecko/20100101 Firefox/81.0

Browser: Firefox 81

Operating system: Linux

Device Platform: Desktop

Date tested: 4 years ago

Test name	Executions per second
getOwnPropertyNames	5192009.0 Ops/sec
for ... in	23440722.0 Ops/sec

Script Preparation code:

var obj = {
  $props : ['a','b','c'],
  a:1,
  b:2,
  c:3
}

AخA
 
var obj = {  $props : ['a','b','c'],  a:1,  b:2,  c:3}

Tests:

const arr = Object.keys(obj);
let n = 0;
for (let i = 0; i < arr.length; i++) {
  const k = arr[i];
  if (k.charAt(0) == '$') continue;
  n++;
}

 
const arr = Object.keys(obj);let n = 0;for (let i = 0; i < arr.length; i++) {  const k = arr[i];  if (k.charAt(0) == '$') continue;  n++;}

let n = 0;
for (const k in obj) {
  if (k.charAt(0) == '$') continue;
  n++;
}

 
let n = 0;for (const k in obj) {  if (k.charAt(0) == '$') continue;  n++;}