Run results for: Splti vs Trim vs replace className

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/133.0.0.0 Safari/537.36

Browser: Chrome 133

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Trim + replace ClassName

10K/s

No Trim - Replace CLassName

7K/s

Split + filter Classname

6K/s

View exact numbers

Test name	Executions per second
✓ Trim + replace ClassName	9,504 Ops/sec
No Trim - Replace CLassName	7,193 Ops/sec
Split + filter Classname	5,822 Ops/sec

HTML Preparation code:

<div id="foo" class="bar test    space  OK"></div>

Script Preparation code:

/*your preparation JavaScript code goes here
To execute async code during the script preparation, wrap it as function globalMeasureThatScriptPrepareFunction, example:*/
async function globalMeasureThatScriptPrepareFunction() {
    // This function is optional, feel free to remove it.
    // await someThing();
}

Tests:

Split + filter Classname
let element = document.getElementById("foo"); let i = 1000; while (i--) { const classes = element.className.split(/\s+/g) if (classes.length) { let selector = `${classes.join('.')}`; if (selector.endsWith('.')) { selector = `.${selector.slice(0, -1)}`; } } }
Trim + replace ClassName
let element = document.getElementById("foo"); let i = 1000; while (i--) { let selector = "." + element.className.trim().replace(/\s+/g, '.'); }
No Trim - Replace CLassName
let element = document.getElementById("foo"); let i = 1000; while (i--) { let selector = "." + element.className.replace(/\s+/g, '.'); if (selector.endsWith('.')) { selector = selector.slice(0, -1); } }