Let's break down what's being tested in this JavaScript microbenchmark.

What is being tested?

The benchmark compares two different ways to access the URL of a webpage: document.location.pathname and document.URL. The goal is to determine which method is faster, more efficient, or has some other desirable property.

Options compared:

1. document.location.pathname: This returns the path part of the current URL. For example, if the URL is /path/to/resource, it will return /path/to.
2. document.URL: This returns the entire URL string. For example, if the URL is /path/to/resource, it will return /path/to/resource.

Pros and Cons:

• document.location.pathname:
  • Pros: Can be faster because it only needs to parse the path part of the URL, which might be a smaller string.
  • Cons: May not include other parts of the URL (like protocol, hostname, or search parameters).
• document.URL:
  • Pros: Includes all parts of the URL, making it more comprehensive.
  • Cons: Might be slower due to the additional processing required.

Library and special JS feature:

There are no libraries mentioned in this benchmark. However, note that some modern browsers have a security feature called same-origin policy, which might affect how document.location behaves when accessing certain properties.

Special JS feature or syntax:

This benchmark does not use any special JavaScript features or syntax beyond standard ECMAScript (JS) syntax.

Other alternatives:

If you wanted to compare these two approaches in a different way, you might consider:

• Using a mock window object with controlled URL values.
• Implementing the URL parsing logic from scratch.
• Using a third-party library that provides an API for working with URLs.
• Adding additional factors to the comparison, such as the number of path segments or query parameters.

However, the current approach allows users to easily compare these two common ways to access the URL in JavaScript, making it a straightforward and accessible benchmark.