Run results for: undefined vs. typeof vs. in vs. hasOwnProperty.call()

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:64.0) Gecko/20100101 Firefox/64.0

Browser: Firefox 64

Operating system: Mac OS X 10.13

Device Platform: Desktop

Date tested: 6 years ago

Script Preparation code:

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

Tests: