Run results for: map vs for of

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/101.0.4951.64 Safari/537.36 Edg/101.0.1210.53

Browser: Chrome 101

Operating system: Windows

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
for in	136.3 Ops/sec
map	184.9 Ops/sec

Script Preparation code:

var itemCount = 10000
var items = new Array(itemCount)

for (var i = itemCount - 1; i >= 0; i--) {
  items[i] = { id: i, data: 920501 }
}

Tests: