Benchmark: Lodash cloneDeep vs structuredClone vs recursiveDeepCopy vs JSON clone vs Fast Copy

HTML Preparation code:

<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>
<script type="module">
  import fastCopy from 'https://cdn.skypack.dev/fast-copy';
  window.fastCopy = fastCopy;
</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;

function recursiveDeepCopy(o) {
    var newO,
      i;
  
    if (typeof o !== 'object') {
      return o;
    }
    if (!o) {
      return o;
    }
  
    if ('[object Array]' === Object.prototype.toString.apply(o)) {
      newO = [];
      for (i = 0; i < o.length; i += 1) {
        newO[i] = recursiveDeepCopy(o[i]);
      }
      return newO;
    }
  
    newO = {};
    for (i in o) {
      if (o.hasOwnProperty(i)) {
        newO[i] = recursiveDeepCopy(o[i]);
      }
    }
    return newO;
  }

Tests:

Lodash cloneDeep
myCopy = _.cloneDeep(MyObject);
Native structuredClone
myCopy = structuredClone(MyObject);
recursiveDeepCopy
myCopy = recursiveDeepCopy(MyObject);
Json Clone
myCopy = JSON.parse(JSON.stringify(MyObject));
Fast Copy
myCopy = fastCopy(MyObject);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Lodash cloneDeep
Native structuredClone
recursiveDeepCopy
Json Clone
Fast Copy

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 12 days ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/135.0.0.0 Safari/537.36 Edg/135.0.0.0

Browser/OS: Chrome 135 on Windows

View result in a separate tab

Test name	Executions per second
Lodash cloneDeep	1804238.1 Ops/sec
Native structuredClone	566283.2 Ops/sec
recursiveDeepCopy	5444247.0 Ops/sec
Json Clone	1559315.1 Ops/sec
Fast Copy	2973227.8 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks and explore what's being tested on MeasureThat.net.

**Benchmark Overview**

The provided JSON defines a benchmark that compares the performance of four different approaches to create a deep copy of an object: Lodash `cloneDeep`, the native `structuredClone` API, a custom recursive function `recursiveDeepCopy`, and a lightweight copying library called Fast Copy. The benchmark also includes the original object `MyObject` with various properties, including nested objects and arrays.

**Options Compared**

1. **Lodash `cloneDeep`**: A widely-used utility library that provides a deep copy of an object.
2. **Native `structuredClone` API**: Introduced in ECMAScript 2020, this is a new way to create a deep copy of an object.
3. **Custom recursive function `recursiveDeepCopy`**: A home-brewed implementation of a deep copy algorithm.
4. **Fast Copy**: A lightweight library designed for fast copying of objects.

**Pros and Cons**

1. **Lodash `cloneDeep`**:
	* Pros: widely used, well-tested, and easy to use.
	* Cons: adds an external dependency (Lodash) and might be slower due to its complexity.
2. **Native `structuredClone` API**:
	* Pros: efficient, modern, and standardized by the ECMAScript standard.
	* Cons: requires a recent browser or JavaScript engine that supports it.
3. **Custom recursive function `recursiveDeepCopy`**:
	* Pros: fast and lightweight, no external dependencies required.
	* Cons: can be error-prone, hard to debug, and might not work for all edge cases.
4. **Fast Copy**:
	* Pros: optimized for performance, small footprint, and easy to use.
	* Cons: relatively unknown compared to other libraries, and its documentation is limited.

**Libraries and APIs**

1. **Lodash**: A popular utility library that provides a wide range of functions for functional programming, including `cloneDeep`.
2. **Fast Copy**: A lightweight library designed specifically for fast copying of objects.
3. **Structured Clone API**: A new way to create a deep copy of an object introduced in ECMAScript 2020.

**Special JS Features and Syntax**

None mentioned explicitly, but the use of the `structuredClone` API implies that it's being tested on a modern JavaScript engine or browser.

**Alternatives**

Other alternatives for creating deep copies of objects include:

1. **JSON.parse(JSON.stringify())**: A simple but inefficient approach that creates a shallow copy.
2. **For...in loops and Object.assign()**: An older, more verbose way to create a deep copy using loops and the `Object.assign()` method.

In summary, this benchmark compares four different approaches to create a deep copy of an object: Lodash `cloneDeep`, the native `structuredClone` API, a custom recursive function `recursiveDeepCopy`, and Fast Copy. The results can help users understand the performance trade-offs between these approaches and choose the best one for their specific use case.

Related benchmarks:

Lodash cloneDeep vs structuredClone vs recursiveDeepCopy vs JSON clone vs Fast Copy (version: 0)

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

Comparing performance of: Lodash cloneDeep vs Native structuredClone vs recursiveDeepCopy vs Json Clone vs Fast Copy

Created: 2 years ago by: Guest

Jump to the latest result

Lodash cloneDeep

Native structuredClone

recursiveDeepCopy

Json Clone

Fast Copy

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):