I'd be happy to explain the benchmark and its results.

Benchmark Definition

The test creates two JavaScript microbenchmarks that compare the performance of JSON.stringify and structuredClone. The goal is to determine which method is faster for creating a deep copy of an object.

Script Preparation Code

The script preparation code defines a JavaScript object MyObject with various properties, including description, myNumber, myBoolean, and jayson. The jayson property contains another object with two properties: stringify and parse.

Html Preparation Code

There is no HTML preparation code provided.

Test Cases

The benchmark consists of two test cases:

1. JSON.stringify: Creates a deep copy of MyObject using JSON.parse(JSON.stringify(MyObject)).
2. structuredClone: Creates a deep copy of MyObject using structuredClone(MyObject).

Library and its Purpose

In this benchmark, the structuredClone library is used to create a deep copy of the object. The structuredClone function was introduced in ECMAScript 2020 as a replacement for JSON.parse(JSON.stringify()). It provides a safer way to clone objects, as it can handle cyclic references and other edge cases.

Special JS Feature or Syntax

There is no special JavaScript feature or syntax used in this benchmark. The only notable aspect is the use of structuredClone, which is a relatively new function introduced in ECMAScript 2020.

Pros and Cons of Different Approaches

The two approaches are:

• JSON.stringify: This method has been widely used for years, but it has some limitations:
  • It can throw errors if the object contains cyclic references or other invalid data.
  • It can be slower than structuredClone due to its parsing steps.
• structuredClone: This method is safer and faster than JSON.stringify, as it avoids parsing and creates a deep copy directly:
  • It handles cyclic references and other edge cases more robustly.
  • It is generally faster than JSON.stringify.

Other Alternatives

Before the introduction of structuredClone, developers used to use JSON.parse(JSON.stringify()) or third-party libraries like Lodash's cloneDeep() function. Both approaches had their limitations, but structuredClone has become the recommended way to create deep copies in modern JavaScript.

In summary, the benchmark shows that structuredClone is generally faster and safer than JSON.stringify for creating deep copies of objects. This is a significant improvement over the older approach, making it easier to write robust and efficient code.