Benchmark: lodash 4.17.21 vs deepmerge 4.3.1

HTML Preparation code:

<script src='https://unpkg.com/lodash@4.17.21/lodash.js'></script>
<script src='https://unpkg.com/deepmerge@4.3.1/dist/umd.js'></script>

Tests:

lodash merge
var a = { a: 'oh', b: 'my', c: { a: 'a', b: { c: 'c' } } }; var b = { c: { b: { d: 'a' }, c: { d: 'd' } } }; var c = _.merge({}, a, b);
deedmerge
var a = { a: 'oh', b: 'my', c: { a: 'a', b: { c: 'c' } } }; var b = { c: { b: { d: 'a' }, c: { d: 'd' } } }; var c = deepmerge({}, a, b);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
lodash merge
deedmerge

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

Let's break down what is tested in the provided JSON.

**Benchmark Definition**

The benchmark tests two JavaScript libraries: Lodash and Deepmerge. Both libraries are used for merging objects, but they have different approaches to achieve this.

*   **Lodash**: Lodash is a utility library that provides a wide range of functions for various tasks, including object manipulation. The `merge` function in Lodash recursively merges two or more objects into one, overwriting any common properties.
*   **Deepmerge**: Deepmerge is a lightweight library specifically designed for merging objects. It provides a simple and efficient way to merge objects, handling nested objects and arrays.

**Options Compared**

The benchmark compares the performance of Lodash's `merge` function with Deepmerge. The main differences in their approaches are:

*   **Recursion vs Iteration**: Lodash uses recursion to merge objects, which can lead to a higher memory footprint and potentially slower performance for very large datasets. Deepmerge, on the other hand, uses iteration, which tends to be more efficient.
*   **Object Comparison**: Lodash compares objects using the `===` operator, whereas Deepmerge uses a custom comparison function that takes into account object properties, such as keys, values, and types.

**Pros and Cons**

*   **Lodash's Recursion**: While recursion can be a powerful tool for solving problems, it may not always be the most efficient approach, especially when dealing with large datasets. However, Lodash's `merge` function is widely adopted and well-maintained.
*   **Deepmerge's Iteration**: Deepmerge's iteration-based approach tends to be faster and more memory-efficient than Lodash's recursion. This makes it a good choice for applications where performance is critical.

**Library-Specific Considerations**

*   **Lodash**: As mentioned earlier, Lodash is a utility library that provides many functions beyond object merging. Its `merge` function is just one of the many features it offers.
*   **Deepmerge**: Deepmerge is designed specifically for merging objects and has a much smaller footprint than Lodash. This makes it a good choice when only object merging is required.

**Special JS Features or Syntax**

There are no special JavaScript features or syntax used in this benchmark. Both Lodash's `merge` function and Deepmerge use standard JavaScript concepts, such as objects and array iteration.

**Other Alternatives**

If you're looking for alternative libraries to merge objects, some popular options include:

*   **Underscore.js**: Another utility library that provides a `merge` function similar to Lodash.
*   **Fusion**: A lightweight object merging library that provides a simple and efficient way to merge objects.
*   **Object.assign()**: A built-in JavaScript method for merging objects, although it can be less efficient than specialized libraries like Deepmerge.

In summary, the benchmark tests the performance of Lodash's `merge` function against Deepmerge by comparing their object merging capabilities. While both libraries have their strengths and weaknesses, Deepmerge's iteration-based approach tends to be faster and more memory-efficient, making it a good choice for applications where performance is critical.

Latest run results:

Run details: (Test run date: 3 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:128.0) Gecko/20100101 Firefox/128.0

Browser/OS: Firefox 128 on Mac OS X 10.15

View result in a separate tab

Test name	Executions per second
lodash merge	294587.0 Ops/sec
deedmerge	379546.6 Ops/sec

Related benchmarks:

lodash 4.17.21 vs deepmerge 4.3.1 (version: 0)

Comparing performance of: lodash merge vs deedmerge

Created: 3 months ago by: Guest

Jump to the latest result

lodash merge

deedmerge

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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