Benchmark: JSON clone vs structuredClone

HTML Preparation code:

<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Script Preparation code:

var MyObject = {
  description: 'Creates a deep copy of source, which should be an object or an array.',
  myNumber: 123456789,
  myBoolean: true,
  jayson: {
    stringify: 'JSON.stringify() method converts a JavaScript value to a JSON string....',
    parse: 'JSON.parse() method parses a JSON string...'
  }
};

var myCopy = null;

Tests:

JSON clone
myCopy = JSON.parse(JSON.stringify(MyObject));
Native structuredClone
myCopy = structuredClone(MyObject);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
JSON clone
Native structuredClone

Fastest: N/A

Slowest: N/A

Latest run results:

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

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Let's dive into the world of JavaScript microbenchmarks.

**Benchmark Overview**

The provided benchmark compares two approaches to create a copy of an object: `JSON.parse(JSON.stringify(MyObject))` and `structuredClone(MyObject)`. The test uses a JavaScript object `MyObject` with nested properties, including a `jayson` property that references other JavaScript objects and functions.

**Options Compared**

There are two options compared in this benchmark:

1. **JSON Clone**: `myCopy = JSON.parse(JSON.stringify(MyObject));`
2. **Native structuredClone**: `myCopy = structuredClone(MyObject);`

**Pros and Cons of Each Approach**

### JSON Clone

* **Pros**:
	+ Widely supported by most browsers, including older versions.
	+ Simple to implement, as it uses the built-in `JSON` object and string manipulation functions.
* **Cons**:
	+ Can lead to issues with cyclic references, where an object points back to itself, causing infinite recursion during cloning.
	+ May not preserve all properties or nuances of the original object, especially if they involve functions, callbacks, or other complex data types.

### Native structuredClone

* **Pros**:
	+ Designed specifically for creating deep copies of objects and arrays, with built-in support for cyclic references and property preservation.
	+ More efficient than JSON clone, as it uses a more optimized algorithm to create the copy.
* **Cons**:
	+ Requires modern JavaScript versions (ECMAScript 2017 or later) and specific browser implementations that support `structuredClone`.
	+ May not be widely supported by older browsers.

**Library Used**

In this benchmark, the `lodash` library is used in the HTML preparation code. However, it's not directly related to the benchmark itself, as the test uses built-in JavaScript functions (`JSON.parse`, `structuredClone`) instead of any custom libraries provided by `lodash`.

**Special JS Features or Syntax**

There are no special JavaScript features or syntaxes mentioned in this benchmark that would require additional explanation.

**Other Alternatives**

If you need to create copies of objects or arrays in your own code, other approaches might be considered:

* **Recursion**: Manually implementing a recursive function to clone the object, which can lead to stack overflows for large inputs.
* **Serialization and Deserialization**: Converting the object to a string (e.g., using `JSON.stringify`) and then parsing it back into an object, which can result in issues with cyclic references or data type changes.
* **Using a Library**: Depending on your specific requirements, you might consider using dedicated libraries like Lodash's `cloneDeep` function, which provides more robust copy creation than the `structuredClone` method.

Keep in mind that these alternatives are not as efficient or reliable as the native `structuredClone` approach and may require more development effort to implement correctly.

Related benchmarks:

JSON clone vs structuredClone (version: 0)

https://developer.mozilla.org/en-US/docs/Web/API/structuredClone

Comparing performance of: JSON clone vs Native structuredClone

Created: 3 years ago by: Guest

Jump to the latest result

JSON clone

Native structuredClone

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):