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

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.132 YaBrowser/20.3.1.195 Yowser/2.5 Yptp/1.23 Safari/537.36

Browser: Yandex Browser 20

Operating system: Windows

Device Platform: Desktop

Date tested: 4 years ago

Test name	Executions per second
ue	4227719.5 Ops/sec
aue	12776396.0 Ops/sec
eu	4196995.5 Ops/sec
eau	12860567.0 Ops/sec

Script Preparation code:

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

Tests:

ue
undefined !== obj.d;
aue
'undefined' !== typeof obj.d;
eu
undefined !== obj.xxxd;
eau
'undefined' !== typeof obj.xxxd;

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

Object lookup performance

ue

aue

eu

eau