Run results for: undefined vs. typeof vs. in vs. hasOwnProperty vs Object.prototype.hasOwnProperty

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:97.0) Gecko/20100101 Firefox/97.0

Browser: Firefox 97

Operating system: Mac OS X 10.15

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
undefined	972844160.0 Ops/sec
typeof	998069376.0 Ops/sec
in	988998976.0 Ops/sec
hasOwnProperty	1017171584.0 Ops/sec
bool	711591680.0 Ops/sec
Object.prototype.hasOwnProperty	2060769.0 Ops/sec

Script Preparation code:

var obj = { a: 1, b: 2, c: 3, d: 4, e: 5 };
function hasOwn (obj, key) {
  return hasOwnProperty.call(obj, key)
}

Tests: