Benchmark: JQuery: selector for find by class

HTML Preparation code:

<div class="test" id="main">
  <div class="innerTest"></div>
  <div class="innerTest"></div>
  <div class="innerTest"></div>
</div>
<script src='https://cdnjs.cloudflare.com/ajax/libs/jquery/3.4.1/jquery.js'></script>

Tests:

$("#main").find(".innerTest")
$("#main").find(".innerTest");
$(".innerTest")
$(".innerTest");
$("#main").children(".innerTest")
$("#main").children(".innerTest");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
$("#main").find(".innerTest")
$(".innerTest")
$("#main").children(".innerTest")

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 4 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Firefox/78.0

Browser/OS: Firefox 78 on Windows

View result in a separate tab

Test name	Executions per second
$("#main").find(".innerTest")	252529.7 Ops/sec
$(".innerTest")	317095.2 Ops/sec
$("#main").children(".innerTest")	143162.0 Ops/sec

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

LLMs can make mistakes. Check important info.

I'll break down the test case and provide an explanation of what's being tested, compared options, pros and cons, and other considerations.

**Benchmark Overview**

The benchmark is designed to measure the performance of different JavaScript approaches for finding elements with a specific class using jQuery. The goal is to determine which approach is the most efficient.

**Test Case 1: `$(" #main ").find( ".innerTest" ");`**

* **Test Name:** `$(" #main ").find( ".innerTest" ");"`
* **Library:** jQuery
* **Purpose:** This test case uses the `find()` method to search for elements with the class "innerTest" within the element with the ID "main".
* **Special JS Feature/Syntax:** None

**Pros:**

* Fast and efficient, as it only traverses up to the first matching element.
* Returns a jQuery object, which can be used for further chaining or manipulation.

**Cons:**

* May not work if there are multiple elements with the class "innerTest" within the parent element.
* Requires an additional iteration over the DOM tree.

**Alternative Approach:** `$( "#main" ).get().map(function() { return $( this).find( ".innerTest" ); });`

This alternative approach uses the `get()` method to retrieve an array of elements from the jQuery object, and then maps each element to a new jQuery object that performs the search. While it may be more efficient than using `find()`, it is also less concise and can be slower due to the additional iteration.

**Test Case 2: `$(".innerTest");`**

* **Test Name:** `$(".innerTest");"`
* **Library:** jQuery
* **Purpose:** This test case uses a simple selector to search for elements with the class "innerTest".
* **Special JS Feature/Syntax:** None

**Pros:**

* Fast and efficient, as it only requires a single DOM lookup.
* Returns an array of matching elements.

**Cons:**

* May not work if there are multiple elements with the class "innerTest" within the current scope.
* Less selective than using `find()` or other methods that consider the parent element's context.

**Alternative Approach:** Using a CSS selector or a more targeted DOM query (e.g., `document.querySelector(".innerTest")`)

This alternative approach is generally faster and more efficient, but may not work in all scenarios. The use of a CSS selector or a DOM query can be less flexible than using jQuery's `find()` method.

**Test Case 3: `$("#main").children( ".innerTest" );`**

* **Test Name:** "$("#main").children( ".innerTest" );"
* **Library:** jQuery
* **Purpose:** This test case uses the `children()` method to search for elements with the class "innerTest" within the element with the ID "main".
* **Special JS Feature/Syntax:** None

**Pros:**

* Fast and efficient, as it only traverses down to direct children.
* Returns an array of matching elements.

**Cons:**

* May not work if there are multiple elements with the class "innerTest" within the parent element (i.e., nested elements).
* Less selective than using `find()` or other methods that consider the parent element's context.

**Alternative Approach:** Using a CSS selector or a more targeted DOM query (e.g., `document.querySelector("#main .innerTest")`)

This alternative approach is generally faster and more efficient, but may not work in all scenarios. The use of a CSS selector or a DOM query can be less flexible than using jQuery's `children()` method.

**Other Considerations:**

* For larger datasets or complex DOM structures, other approaches like using `filter()` or `forEach()` might be necessary.
* Performance optimizations should also consider the browser and JavaScript engine used.
* The benchmark results may not reflect real-world scenarios, as they are limited to a single HTML page with a specific structure.

**Alternatives:**

* For this specific test case, alternative approaches like using CSS selectors or more targeted DOM queries (e.g., `document.querySelector(".innerTest")`) can be faster and more efficient.
* Other JavaScript libraries like vanilla JavaScript or other query-based libraries might also be used for similar tasks.
* Consider using more modern JavaScript features and optimizations, such as async/await or Web Workers, to improve performance in complex scenarios.

Related benchmarks:

JQuery: selector for find by class (version: 0)

Test different approach for found by class

Comparing performance of: $("#main").find(".innerTest") vs $(".innerTest") vs $("#main").children(".innerTest")

Created: 4 years ago by: Guest

Jump to the latest result

$("#main").find(".innerTest")

$(".innerTest")

$("#main").children(".innerTest")

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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