Benchmark: querySelector vs Closest!

HTML Preparation code:

<div><div><div>

<div data-parent="parent-id">

  <div><div>

    <div data-target="target-id">

      <div><div>

        <div data-clicked="clicked-id"></div>

      </div></div>

    </div>

  </div></div>

</div>

</div></div></div>

Tests:

Closest?
document.querySelector('[data-clicked]').closest('[data-target]')
querySelector?
document.querySelector('[data-parent="parent-id"]:has([data-target="target-id"])')

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Closest?
querySelector?

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.36

Browser/OS: Chrome 125 on Windows

View result in a separate tab

Test name	Executions per second
Closest?	1239539.9 Ops/sec
querySelector?	510912.6 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark JSON and explain what is being tested, compared, and other considerations.

**Benchmark Definition**

The benchmark measures the performance difference between two approaches to find elements with specific attributes in an HTML document using JavaScript: `querySelector` vs `closest`.

**Options Compared**

1. **`document.querySelector('[data-clicked]').closest('[data-target]')`**: This approach uses the `querySelector` method to select an element with the attribute `[data-clicked]`, and then calls the `closest` method on that element to find another element with the attribute `[data-target]`.
2. **`document.querySelector('[data-parent="parent-id"]:has([data-target="target-id"])')`**: This approach uses the `querySelector` method to select an element with the attribute `[data-parent="parent-id"]`, and then calls the `has` method on that element to check if it contains another element with the attribute `[data-target="target-id"]`.

**Pros and Cons of Each Approach**

1. **`document.querySelector('[data-clicked]').closest('[data-target]')`**:
	* Pros: Simple and straightforward.
	* Cons: May perform unnecessary checks or traversals to find the closest matching element, leading to potential performance overhead.
2. **`document.querySelector('[data-parent="parent-id"]:has([data-target="target-id"])')`**:
	* Pros: More efficient, as it allows the browser to short-circuit the search once it finds a parent element with the specified attribute.
	* Cons: May be slower for very deep or complex DOM trees.

**Library and Purpose**

There is no explicit library mentioned in the benchmark definition. However, `querySelector` and `closest` are built-in methods provided by modern browsers' JavaScript APIs.

**Special JS Features or Syntax**

None are explicitly mentioned, but the use of attribute selectors (`[data-clicked]`, `[data-target]`) and the `:has` pseudo-class are supported by most modern browsers.

**Other Considerations**

* The benchmark uses a relatively simple HTML structure with nested elements, which may not accurately represent real-world scenarios.
* The test cases focus on performance, but do not account for factors like memory allocation or garbage collection, which could impact overall system performance.
* Alternative approaches, such as using CSS selectors or other libraries (e.g., jQuery), are not being tested in this benchmark.

**Alternative Alternatives**

Other approaches to find elements with specific attributes include:

1. Using `querySelectorAll` and iterating over the result set to find matching elements.
2. Utilizing browser-specific APIs like `Element.matches()` or `DOMTokenList`.
3. Leveraging third-party libraries, such as jQuery, which provides a more comprehensive set of utility methods for working with DOM elements.

Keep in mind that these alternatives may introduce additional overhead or complexity, so it's essential to evaluate their performance and suitability for specific use cases.

Related benchmarks:

querySelector vs Closest! (version: 0)

Comparing performance of: Closest? vs querySelector?

Created: 2 years ago by: Guest

Jump to the latest result

Closest?

querySelector?

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):