Benchmark: style vs. style.cssText single

HTML Preparation code:

<div id='a'>foo</div>
<div id='b'>bar</div>

Script Preparation code:

var a = document.getElementById('a');
var b = document.getElementById('b');

Tests:

style
a.style.fontSize = `${20 * Math.random()}px`; const x = a.getBoundingClientRect();
style.cssText
b.style.cssText = `font-size: ${20 * Math.random()}px;`; const x = b.getBoundingClientRect();

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
style
style.cssText

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

This benchmark does not have any results yet. Be the first one to run it!

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

LLMs can make mistakes. Check important info.

Let's break down the benchmarking scenario and explain what's being tested.

**Benchmark Setup**

The benchmark uses two HTML elements (`<div id="a">` and `<div id="b">`) to measure the performance of setting styles on elements. The `Script Preparation Code` sets up two variables, `a` and `b`, which represent these elements using `document.getElementById`. The `Html Preparation Code` defines the HTML structure with both elements.

**Benchmark Variants**

There are two test cases:

1. **"style"`**: This variant tests setting a style property on an element directly (in this case, `a.style.fontSize = ...`). It calculates the random font size and then gets the element's bounding rectangle using `getBoundingClientRect()`.
2. **"style.cssText"`**: This variant tests setting a CSS text property on an element using a string (in this case, `b.style.cssText = 'font-size: ...'`). Similar to the first test, it calculates the random font size and then gets the element's bounding rectangle.

**Library Usage**

Neither of these variants explicitly uses any libraries. However, if we were to analyze the code, we could say that `getBoundingClientRect()` is a standard JavaScript function provided by modern browsers, which is part of the DOM API (Document Object Model). This library-like component is part of the browser's core functionality.

**Special JS Features or Syntax**

There are no special JS features or syntax used in these benchmark variants. They appear to be straightforward, typical JavaScript code snippets.

**Pros and Cons of Different Approaches**

1. **Direct Style Setting (`style`)**:
	* Pros: Simple, easy to understand, and widely supported.
	* Cons: May not be as efficient for large styles or when working with many elements, as it requires parsing the style string.
2. **CSS Text Setting (`style.cssText`)**:
	* Pros: Can be more efficient than direct style setting, as it only requires updating a single CSS property value, which can be cached by browsers.
	* Cons: Requires using a string and parsing it for the CSS syntax, which might introduce minor performance overhead.

**Other Alternatives**

If you were to benchmark alternative approaches, some possible variants could include:

* Using `style` with a specific unit (e.g., `a.style.fontSize = '20px';`)
* Using a different method for calculating the random font size (e.g., using `Math.random()` directly instead of multiplying it by 20)
* Adding additional styles to the element to simulate real-world scenarios
* Using a CSS-in-JS library or preprocessor to generate and apply styles

Keep in mind that these alternatives would likely alter the benchmark's outcome, as they might introduce different performance characteristics or complexities.

Overall, this benchmark is testing the performance of two common methods for setting styles on elements: direct style setting and using `style.cssText`.

Related benchmarks:

style vs. style.cssText single (version: 0)

Comparing performance of: style vs style.cssText

Created: 4 years ago by: Guest

Jump to the latest result

style

style.cssText

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):