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

Run details:

User agent: Mozilla/5.0 (Linux; Android 10; 6201) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.114 Mobile Safari/537.36 OPR/64.2.3282.60128

Browser: Opera Mobile 64

Operating system: Android

Device Platform: Mobile

Date tested: 3 years ago

Test name	Executions per second
undefined	433121.7 Ops/sec
typeof	1198944.6 Ops/sec
in	1182880.2 Ops/sec
hasOwnProperty	1089169.2 Ops/sec
bool	1181367.5 Ops/sec
?.	1166822.1 Ops/sec

Script Preparation code:

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

Tests:

undefined
undefined !== obj.d;
typeof
'undefined' !== typeof obj.d;
in
'd' in obj;
hasOwnProperty
obj.hasOwnProperty( 'd' );
bool
!! obj.d;
?.
obj?.d

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

Object lookup performance

undefined

typeof

in

hasOwnProperty

bool

?.