I'll dive into explaining the benchmark.

What is being tested?

MeasureThat.net is testing three different approaches to check if an HTML element has a display property set to none. The elements are checked using:

1. window.getComputedStyle(document.getElementById(element), null).getPropertyValue("display").indexOf('none') === -1: This approach uses the getComputedStyle() method to get the computed style of the element, specifically the value of the display property. It then checks if the indexOf('none') returns -1, which means the display property is not set to none.
2. document.getElementById(element).className.indexOf('hide') === -1: This approach uses the className property of the element to check if it contains the string 'hide'. The idea is that if the element has a class named hide, its display property should be set to none.
3. document.getElementById(element).classList.contains('hide'): This approach uses the classList property (introduced in HTML5) to check if the element contains the string 'hide'. Similar to the previous approach, it assumes that having a class named hide means its display property is set to none.

Options compared

The three approaches are being compared to determine which one is the most efficient.

Pros and cons of each approach:

1. window.getComputedStyle():
   • Pros:
     • Accurate, as it gets the actual computed style of the element.
   • Cons:
     • Can be slower due to the extra overhead of getting the computed style.
2. className:
   • Pros:
     • Simple and straightforward.
   • Cons:
     • May not work in all cases (e.g., if the display property is set using CSS styles that are not included in the element's class list).
3. classList.contains():
   • Pros:
     • More modern and widely supported than the className approach.
   • Cons:
     • May also have issues with certain CSS styles or class names.

Library used

None of these approaches use any specific libraries, but they do rely on built-in JavaScript features like window.getComputedStyle(), document.getElementById(), and classList.

Special JS feature/syntax

No special JavaScript features or syntax are used in this benchmark. It only relies on standard JavaScript features.

Other alternatives

There may be other approaches to check if an element has a display property set to none. Some possible alternatives include:

• Using CSS selectors (e.g., :empty or ::before pseudo-classes) to detect the presence of a class named hide.
• Using the style property directly instead of relying on window.getComputedStyle().
• Using a library like jQuery to simplify the code and make it more efficient.

However, these alternatives are not being tested in this benchmark.