Run results for: Getting a context: while loop nodeName check vs while loop instanceof vs while loop constructor

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/111.0.0.0 Safari/537.36

Browser: Chrome 111

Operating system: Linux

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
while loop + tagName check	365.7 Ops/sec
while loop + instanceof check	122.5 Ops/sec
while loop + consturctor check	153.1 Ops/sec

HTML Preparation code:

<contextprovider id="provider">
  <div>
    <div></div>
    <div></div>
    <div></div>
    <div></div>
    <div>
      <div>
        <span>
          <span>
            <span>abc</span>
          </span>
          def
          <span>
            <span id="foo"></span>
          </span>
        </span>
      </div>
      ghi
    </div>
  </div>
</contextprovider>

Script Preparation code:

var context = document.getElementById('provider');
var element = document.getElementById('foo');

Tests:

while loop + tagName check
var i = 5000; while (i--) { let ctx = element; while (ctx && ctx.nodeName !== 'CONTEXTPROVIDER') { ctx = ctx.assignedSlot || ctx.parentNode || ctx.host; } if (ctx !== context) { throw new Error('mismatch'); } }
while loop + instanceof check
var i = 5000; while (i--) { let ctx = element; while (ctx && !(ctx instanceof HTMLUnknownElement)) { ctx = ctx.assignedSlot || ctx.parentNode || ctx.host; } if (ctx !== context) { throw new Error('mismatch'); } }
while loop + consturctor check
var i = 5000; while (i--) { let ctx = element; while (ctx && ctx.constructor !== HTMLUnknownElement) { ctx = ctx.assignedSlot || ctx.parentNode || ctx.host; } if (ctx !== context) { throw new Error('mismatch'); } }

Run results for: Getting a context: while loop nodeName check vs while loop instanceof vs while loop constructor

while loop + tagName check

while loop + instanceof check

while loop + consturctor check