Run results for: null vs. hasOwnProperty

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 15_4_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) FxiOS/100.1 Mobile/15E148 Safari/605.1.15

Browser: Mobile Safari 15

Operating system: iOS 15.4.1

Device Platform: Mobile

Date tested: 2 years ago

Test name	Executions per second
exist null	17353980.0 Ops/sec
exist hasOwnProperty	16080690.0 Ops/sec
nonexist null	17381830.0 Ops/sec
nonexist hasOwnProperty	16635240.0 Ops/sec

Script Preparation code:

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

Tests:

exist null
obj.d != null;
exist hasOwnProperty
obj.hasOwnProperty( 'd' );
nonexist null
obj.f != null;
nonexist hasOwnProperty
obj.hasOwnProperty( 'f' );

Run results for: null vs. hasOwnProperty

Object lookup performance

exist null

exist hasOwnProperty

nonexist null

nonexist hasOwnProperty