Run results for: Object in vs Object[]

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/77.0.3865.90 Safari/537.36

Browser: Chrome 77

Operating system: Windows

Device Platform: Desktop

Date tested: 4 years ago

Test name	Executions per second
Object in	1187492.0 Ops/sec
direct	1349395.0 Ops/sec

Script Preparation code:

  var object = {},
      array = [],
      i, test = 1000;
  
  for (i = 0; i < 1000; i++) {
   object['something' + i] = true;
   array.push('something' + i);
  }

Tests:

Object in
('something' + test) in object
direct
object['something' + test]

Run results for: Object in vs Object[]

Object in

direct