Let's dive into the world of MeasureThat.net and explore what's being tested in this benchmark.

Benchmark Definition

The benchmark is testing two approaches to extract a specific substring from a date string: Array.split and Substring.

What are we comparing?

We're comparing the performance of two different methods:

1. Array.split: This method splits the date string into an array using the split() method, and then takes the first element of the resulting array.
2. Substring: This method uses the substring() method to extract a specific substring from the date string.

Pros and Cons

Here's a brief overview of each approach:

• Array.split:
  • Pros: Can be more efficient for certain use cases, as it avoids creating a new string object.
  • Cons: Requires creating an array, which can incur overhead. Additionally, if the split character is not present in the string, it will still create an empty array.
• Substring:
  • Pros: Straightforward and easy to read. Avoids creating arrays or objects.
  • Cons: May be slower due to the overhead of creating a new string object.

In general, Array.split can be more efficient when used correctly, but it may incur unnecessary overhead if the split character is not present in the string. On the other hand, Substring is simpler and easier to read, but may be slower due to the creation of a new string object.

Library

There isn't a specific library being tested here. The tests are using built-in JavaScript methods: split() and substring().

Special JS Feature or Syntax

Neither approach uses any special JavaScript features or syntax.

Other Alternatives

If we were to test alternative approaches, some options could be:

• Using regular expressions (e.g., RegExp.test()) instead of Array.split or Substring.
• Using a library like Lodash's string.prototype.split() or string.prototype.trimStart() for more efficient string manipulation.
• Testing different browsers' behavior using the same test cases.

Benchmark Preparation Code

The provided code sets up a date string variable s1 and prepares it for testing. The HTML preparation code is empty, suggesting that this benchmark is purely focused on JavaScript performance.

Overall, this benchmark provides a useful comparison between two common approaches to extracting substrings from strings in JavaScript.