Benchmark: contains vs closest3

HTML Preparation code:

<div id='div1'>
  <div id='div2'>
    <div id='div3'>
    </div>
  </div>
</div>

Tests:

contains
const box = document.getElementById('div1') const clicked = document.getElementById('div3') const isClickInside = box.contains(clicked); return isClickInside
closest
const box = document.getElementById('div1') const clicked = document.getElementById('div3') const isClickInside = clicked.closest('#div1'); return isClickInside

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
contains
closest

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.

I'll break down the provided JSON and explain what's being tested, compared, and discussed.

**Benchmark Definition**

The benchmark definition consists of two test cases: `contains` and `closest`. Both tests aim to measure the performance difference between using the `contains()` method versus the `closest()` method on DOM elements.

**Script Preparation Code**

The script preparation code is empty, which means that the benchmark doesn't perform any initialization or setup before running the tests. This is likely done to minimize overhead and focus solely on the comparison of the two methods.

**HTML Preparation Code**

The HTML preparation code defines a simple nested DOM structure with three elements: `div1`, `div2`, and `div3`. The purpose of this structure is to provide a realistic scenario for testing the containment method.

**Test Cases**

Each test case consists of a single benchmark definition that specifies:

1. **JavaScript Code**: A small snippet of JavaScript code that demonstrates how to use either the `contains()` or `closest()` method on DOM elements.
2. **Test Name**: A descriptive name for each test case, indicating whether it's testing the `contains()` or `closest()` method.

Here are some pros and cons of using these two methods:

**`contains()` Method**

Pros:

* Simple to implement and understand
* Widely supported across modern browsers

Cons:

* Can be slower due to the overhead of traversing the DOM tree
* May not perform well on large or complex DOM structures

**`closest()` Method (using `querySelectorClosest`)**

Pros:

* More efficient than `contains()` since it uses a more optimized algorithm for finding the closest element
* Reduces DOM traversal overhead

Cons:

* Less widely supported across older browsers
* May require additional setup or polyfills if not using modern browsers

**Library and Purpose**

In this benchmark, the `querySelectorClosest` method is used to implement the `closest()` functionality. This method is part of the W3C CSSOM (CSS Object Model) specification and provides a standardized way to find the closest element that matches a given selector.

The use of `querySelectorClosest` allows for more efficient DOM traversals and reduces the likelihood of false positives or negatives, making it a better choice for this specific benchmark.

**Other Considerations**

* The test cases don't account for edge cases such as nested elements with multiple containers.
* There's no consideration for the impact of other factors like JavaScript engine optimizations, caching, or concurrent execution on performance.

**Alternatives**

If you were to create a similar benchmark without using `querySelectorClosest`, you could consider implementing a custom algorithm that traverses the DOM tree to find the closest element. However, this approach would likely result in slower performance and reduced accuracy due to the added overhead of manual traversal and comparison.

Alternatively, you could explore other methods like using `getElementsByClassName` or creating a recursive function to traverse the DOM tree. However, these approaches would likely be less efficient and less accurate than using the optimized `closest()` method provided by `querySelectorClosest`.

Related benchmarks:

contains vs closest3 (version: 0)

Comparing performance of: contains vs closest

Created: 3 years ago by: Guest

Jump to the latest result

contains

closest

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):