Benchmark: Spread Operator vs Lodash

HTML Preparation code:

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

Script Preparation code:

var arr = new Array(100000000).fill(0);

Tests:

Spread Operator
[...arr];
Lodash Clone
_.clone(arr);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Spread Operator
Lodash Clone

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 5 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/142.0.0.0 Safari/537.36

Browser/OS: Chrome 142 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Spread Operator	12.3 Ops/sec
Lodash Clone	0.5 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down what's being tested in the provided benchmark.

**Overview**

The benchmark compares two approaches to creating a shallow clone of an array: the spread operator (`[...arr]`) and Lodash's `clone()` function. The test case uses a large array with 100 million elements, filled with zeros.

**Options Compared**

There are two options being compared:

1. **Spread Operator**: The `[...arr]` syntax creates a new array by spreading the elements of the original array (`arr`) into a new array.
2. **Lodash Clone**: Lodash's `clone()` function creates a deep clone of the original array, which includes all its properties and nested objects.

**Pros and Cons**

1. **Spread Operator**:
	* Pros: Lightweight, easy to understand, and widely supported in modern browsers.
	* Cons: May not be as efficient as other approaches for very large arrays, as it requires creating a new array with the same number of elements.
2. **Lodash Clone**:
	* Pros: Provides a safe and predictable way to create a deep clone of an array, which can help prevent unexpected behavior due to shared mutable objects.
	* Cons: Requires including Lodash in your project, and may be overkill for simple cloning tasks.

**Library: Lodash**

Lodash is a popular JavaScript library that provides various utility functions, including `clone()` for creating deep clones of arrays, objects, and other data structures. The `clone()` function returns a new object with the same properties as the original object, but with no shared references to the original.

**Special JS Feature/Syntax**

There isn't any special JavaScript feature or syntax being used in this benchmark. However, it's worth noting that Lodash is not a part of the standard JavaScript library, so it requires including an external dependency (`lodash.min.js`).

**Other Considerations**

When choosing between these two approaches, consider the following factors:

* Performance: If you need to clone large arrays frequently, the spread operator might be faster due to its lightweight nature. However, if you need a deep clone for safety or predictability, Lodash's `clone()` function is a better choice.
* Code Readability and Maintainability: The spread operator is often easier to understand and write, but may require more whitespace and careful handling of edge cases.

**Alternatives**

Other alternatives to the spread operator and Lodash's `clone()` function include:

1. **Array.prototype.slice() + Array.prototype.concat()**: Creates a shallow copy of the original array.
2. **JSON.parse(JSON.stringify())**: Creates a deep clone of the original array, but can be slower for very large arrays due to the overhead of JSON serialization.
3. **Array.from(arr)`: Creates a new array from an iterable, including the spread operator.

Each alternative has its pros and cons, and the choice ultimately depends on your specific use case and performance requirements.

Related benchmarks:

Spread Operator vs Lodash (version: 2)

Answering https://stackoverflow.com/questions/58702513/lodash-clone-array-vs-spread-operator#

Comparing performance of: Spread Operator vs Lodash Clone

Created: 6 years ago by: Registered User

Jump to the latest result

Spread Operator

Lodash Clone

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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