Run results for: object property lookup: in operator vs undefined comparison

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/135.0.0.0 Safari/537.36

Browser: Chrome 135

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
in operator	23867146.0 Ops/sec
!==undefined comparison	21404310.0 Ops/sec

Script Preparation code:

var obj={prop:'dddd'};

Tests: