Benchmark: Traverse function vs NodeIterator vs TreeWalker (elements)

Script Preparation code:

// language=HTML
const html = `
    <!-- 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 -->
`;
const template = document.createElement('template');
template.innerHTML = html;

window.testTemplate = template;

Tests:

Traverse function
const elements = []; function traverse(node) { if (!node) return; if (node.nodeType === Node.ELEMENT_NODE) { elements.push(node); } traverse(node.nextElementSibling); traverse(node.firstElementChild); } traverse(testTemplate.content.firstElementChild); if (elements.length !== 9) throw new Error(`Expected 9 elements, got ${elements.length}`);
NodeIterator with filter function
const nodeIterator = document.createNodeIterator( testTemplate.content, NodeFilter.SHOW_ALL, { acceptNode(node) { if (node.nodeType === Node.ELEMENT_NODE) { return NodeFilter.FILTER_ACCEPT; } return NodeFilter.FILTER_REJECT; } } ); const elements = []; while (nodeIterator.nextNode()) { elements.push(nodeIterator.currentNode); } if (elements.length !== 9) throw new Error(`Expected 9 elements, got ${elements.length}`);
NodeIterator with filter param
const nodeIterator = document.createNodeIterator( testTemplate.content, NodeFilter.SHOW_ELEMENT ); const elements = []; while (nodeIterator.nextNode()) { elements.push(nodeIterator.currentNode); } if (elements.length !== 9) throw new Error(`Expected 9 elements, got ${elements.length}`);
TreeWalker with filter function
const treeWalker = document.createTreeWalker( testTemplate.content, NodeFilter.SHOW_ALL, { acceptNode(node) { if (node.nodeType === Node.ELEMENT_NODE) { return NodeFilter.FILTER_ACCEPT; } return NodeFilter.FILTER_REJECT; } } ); const elements = []; while (treeWalker.nextNode()) { elements.push(treeWalker.currentNode); } if (elements.length !== 9) throw new Error(`Expected 9 elements, got ${elements.length}`);
TreeWalker with filter param
const treeWalker = document.createTreeWalker( testTemplate.content, NodeFilter.SHOW_ELEMENT ); const elements = []; while (treeWalker.nextNode()) { elements.push(treeWalker.currentNode); } if (elements.length !== 9) throw new Error(`Expected 9 elements, got ${elements.length}`);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Traverse function
NodeIterator with filter function
NodeIterator with filter param
TreeWalker with filter function
TreeWalker with filter param

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):

LLMs can make mistakes. Check important info.

Let's break down what's being tested in this benchmark.

**Benchmark Goal:**
The goal of this benchmark is to compare the speed of three different ways to traverse a DOM tree (a hierarchical structure used by web browsers to represent and manipulate HTML documents).

**Test Cases:**

1. **Traverse function**: This test case uses a recursive function to traverse the DOM tree, starting from the first child element (`testTemplate.content.firstElementChild`). The function checks if each node is an `ELEMENT_NODE` and pushes it to an array.
2. **NodeIterator with filter function**: This test case creates a NodeIterator, which allows for traversing nodes in the DOM tree, but with a custom filter function. In this case, the filter function rejects elements that are not `ELEMENT_NODE`, ensuring only element nodes are visited. The iterator is used to push node references to an array.
3. **NodeIterator with filter param**: This test case creates a NodeIterator similar to the previous one, but without the custom filter function. Instead, it uses a fixed filter parameter (`NodeFilter.SHOW_ELEMENT`) that accepts only `ELEMENT_NODE` nodes by default.
4. **TreeWalker with filter function**: This test case creates a TreeWalker iterator, which traverses the DOM tree in a more efficient way than traditional recursive traversal methods. The custom filter function ensures only `ELEMENT_NODE` nodes are visited.
5. **TreeWalker with filter param**: This test case creates a TreeWalker iterator similar to the previous one, but without the custom filter function.

**Comparison:**

* Traverse function vs NodeIterator (with filter function): Both approaches reject non-element nodes, but the traverse function is likely slower due to its recursive nature.
* Traverse function vs TreeWalker (with filter function): The TreeWalker approach is expected to be faster than the traverse function, as it's optimized for traversing DOM trees in a more efficient manner.
* NodeIterator (with filter param) vs TreeWalker (with filter param): Both approaches accept all element nodes by default, but the tree walker may still outperform the node iterator due to its optimized traversal algorithm.

**Benchmark Results:**
The latest benchmark results show that:

* Traverse function is relatively slow
* TreeWalker with filter param is faster than NodeIterator with filter param
* TreeWalker with filter function is slightly slower than TreeWalker with filter param

In general, these results suggest that the tree walker approach is a good choice when traversing DOM trees in performance-critical code paths.

Latest run results:

Run details: (Test run date: 23 days ago)

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:131.0) Gecko/20100101 Firefox/131.0

Browser/OS: Firefox 131 on Linux

View result in a separate tab

Test name	Executions per second
Traverse function	4022718.0 Ops/sec
NodeIterator with filter function	103098.7 Ops/sec
NodeIterator with filter param	1703766.1 Ops/sec
TreeWalker with filter function	95947.6 Ops/sec
TreeWalker with filter param	1571171.5 Ops/sec

Related benchmarks:

Traverse function vs NodeIterator vs TreeWalker (elements) (version: 0)

Let's compare the speed of 3 different ways to traverse the DOM.

Comparing performance of: Traverse function vs NodeIterator with filter function vs NodeIterator with filter param vs TreeWalker with filter function vs TreeWalker with filter param

Created: one month ago by: Guest

Jump to the latest result

Traverse function

NodeIterator with filter function

NodeIterator with filter param

TreeWalker with filter function

TreeWalker with filter param

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):