Run results for: jsj 4 undefined vs. typeof vs. in vs. hasOwnProperty

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/73.0.3683.75 Safari/537.36

Browser: Chrome 73

Operating system: Mac OS X 10.14.3

Device Platform: Desktop

Date tested: 5 years ago

Script Preparation code:

var obj = { a: 1, b: 2, c: 3, d: 4, e: 5 };
var foo = 'undefined';

Tests: