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

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/12.0 Safari/605.1.15

Browser: Safari 12

Operating system: Mac OS X 10.14

Device Platform: Desktop

Date tested: 3 years ago

Script Preparation code:

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

Tests: