Run results for: Instanceof vs string comparison vs property checking vs constructor comparison 2

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.11; rv:78.0) Gecko/20100101 Firefox/78.0

Browser: Firefox 78

Operating system: Mac OS X 10.11

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
instanceof	39507120.0 Ops/sec
string type	86508840.0 Ops/sec
string type + undefined	34966680.0 Ops/sec
property	33149460.0 Ops/sec
constructor comparison	40121510.0 Ops/sec

HTML Preparation code:

<script>
class TestClass {
    constructor() {
        this.a = 2;
  
        this.b = 'hello';
        this.c = ['some','thing'];
        this.d = [1,1,2,3,5,8,13,21];
        this.e = 'foofoofoo';
        this.f = 'barbarbar';
        this.g = {foo:'bar',12:34};
        this.h = {nested:{nestedMore:{nestedEvenMore:'nah'}}};
  
        this.t = 'mesh';
    }
}
</script>

Script Preparation code:

var obj = new TestClass();

Tests:

instanceof
obj instanceof TestClass;
string type
obj.t === 'mesh'
string type + undefined
obj.t !== undefined
property
obj.a !== undefined
constructor comparison
obj.constructor === TestClass

Run results for: Instanceof vs string comparison vs property checking vs constructor comparison 2

Measure the performance of instanceOf operator vs comparing a basic string type. but more properties

instanceof

string type

string type + undefined

property

constructor comparison