Benchmark: Fork TreeWalker vs querySelectorAll (* all elements)2

HTML Preparation code:

<!-- article out start -->
<article>
  <!-- article in start -->
  <h1>Lorem ipsum</h1>
  <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Cumque, nostrum.</p>
  <!-- article in end -->
</article>
<!-- article out end -->

<!-- article out start -->
<article>
  <!-- article in start -->
  <h1>Lorem ipsum</h1>
  <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Cumque, nostrum.</p>
  <!-- article in end -->
</article>
<!-- article out end -->

<!-- article out start -->
<article>
  <!-- article in start -->
  <h1>Lorem ipsum</h1>
  <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Cumque, nostrum.</p>
  <!-- article in end -->
</article>
<!-- article out end -->

Script Preparation code:

window.treeWalker = document.createTreeWalker(
  document.body,
  NodeFilter.SHOW_ELEMENT
);

Tests:

querySelectorAll
const list = document.body.querySelectorAll('*');
Tree
const list=[]; let el; while(el=treeWalker.nextNode()){ list.push(el); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
querySelectorAll
Tree

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

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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 and explain what is being tested.

**Benchmark Definition**
The benchmark compares two approaches to traverse an HTML document: using `querySelectorAll` (a method from the DOM API) versus using a custom tree walker implementation (`Fork TreeWalker`).

**Options Compared**

1. **querySelectorAll**: This method returns all elements that match a given selector within a given root node. In this case, it's used to select all elements (`*`) in the `document.body`.
2. **Custom Tree Walker (Fork)**: A custom tree walker implementation is created using the `createTreeWalker` method and the `NodeFilter.SHOW_ELEMENT` filter. This implementation traverses the document body and pushes each element into a list.

**Pros and Cons of Each Approach**

1. **querySelectorAll**:
	* Pros:
		+ Efficient for large documents, as it uses a single DOM query.
		+ Fast execution, thanks to browser optimizations.
	* Cons:
		+ May be slower for very small documents or simple queries.
		+ Can lead to unnecessary DOM recalculations if the selector is complex.
2. **Custom Tree Walker (Fork)**:
	* Pros:
		+ More control over the traversal process, allowing for fine-grained optimization.
		+ Can be more efficient for very large documents or specific use cases.
	* Cons:
		+ More complex to implement and maintain.
		+ May have overhead due to creating a custom tree walker.

**Library Usage**
In this benchmark, there is no explicit library usage. However, the `createTreeWalker` method and `NodeFilter.SHOW_ELEMENT` filter are part of the DOM API, which is a built-in JavaScript library.

**Special JS Feature/Syntax**
There is no special JavaScript feature or syntax being used in this benchmark. It's a straightforward implementation of tree walking using the DOM API.

**Other Considerations**

* The benchmark uses an iPhone 15 device and Mobile Safari 15 as the test platform, which may introduce some biases due to differences between mobile browsers.
* The use of `window.treeWalker` suggests that the custom tree walker implementation is being run in a browser environment, but it's not clear if this code will work in other environments.

**Alternatives**

Other alternatives for traversing HTML documents include:

1. **DocumentFragment**: A lightweight alternative to DOM elements, which can be used to traverse and manipulate document content.
2. **ElementIterator**: An iterator-like API that allows for efficient traversal of DOM elements without the need for tree walking or custom implementations.
3. **Pseudo-Element Traversal**: Some browsers support pseudo-element traversal using methods like `querySelector` with a pseudo-element selector (e.g., `:first-child`).

Keep in mind that each alternative has its pros and cons, and the choice of traversal method depends on the specific use case and performance requirements.

Related benchmarks:

Fork TreeWalker vs querySelectorAll (* all elements)2 (version: 0)

Comparing performance of: querySelectorAll vs Tree

Created: 3 years ago by: Guest

Jump to the latest result

querySelectorAll

Tree

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

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