Benchmark: lodash merge vs deepmerge 4.2.2

HTML Preparation code:

<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

<script src='https://unpkg.com/deepmerge@4.2.2/dist/umd.js'></script>

Script Preparation code:

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);

Tests:

lodash
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);
deepmerge
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
deepmerge

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 25 days ago):

LLMs can make mistakes. Check important info.

Let's break down what's being tested in this benchmark.

**Benchmark Overview**

The benchmark compares the performance of two JavaScript libraries: Lodash and DeepMerge (version 4.2.2). The test case uses two objects, `a` and `b`, with nested structures, to simulate a common use case for merging two objects.

**Options Compared**

The benchmark tests the following options:

1. **Lodash**: Specifically, it tests the `_merge()` function from Lodash.
2. **DeepMerge**: A pure JavaScript library designed for merging objects without the need for Lodash or other dependencies.

**Pros and Cons of Each Approach**

**Lodash:**

Pros:

* Wide support in popular JavaScript frameworks (e.g., React, Angular)
* Mature ecosystem with many plugins and utilities
* Well-documented and actively maintained

Cons:

* Additional dependency required (approximately 30KB gzipped)
* May not be suitable for smaller projects or those targeting older browsers
* Not designed specifically for pure JavaScript performance optimization

**DeepMerge:**

Pros:

* Lightweight (approximately 15KB gzipped) and minimal dependencies
* Specifically designed for merging objects without additional libraries
* Fast and optimized for performance

Cons:

* Smaller community compared to Lodash, which may impact support and documentation quality
* Not as widely supported in popular frameworks or older browsers

**Library Purpose**

The `lodash` library is a comprehensive collection of utility functions for functional programming tasks. It provides a wide range of features beyond object merging, such as array manipulation, functional operations, and more.

In the context of this benchmark, Lodash's `_merge()` function is used to combine two objects into one. The function takes an optional third argument (the result) and merges objects using a specified strategy (defaulting to `deep` if not provided).

The `deepmerge` library, on the other hand, is specifically designed for merging objects in a deep, recursive manner without relying on additional libraries like Lodash.

**Special JS Feature or Syntax**

Neither of the tested libraries utilizes any special JavaScript features or syntax. However, both implementations take advantage of JavaScript's built-in object properties and methods (e.g., `Object.assign()`, `{ property: value }`) to perform their respective merging operations.

Other Alternatives

For those looking for alternative approaches:

1. **Underscore.js**: Another popular utility library that includes a `_merge()` function similar to Lodash.
2. **JSON Merge Patch**: A lightweight JavaScript library specifically designed for merging JSON objects in a patch-based approach.
3. **JSON Merge Sort**: An alternative sorting method for object merges, which can be used instead of the traditional deep recursive merge.

Keep in mind that each alternative has its own trade-offs and suitability for specific use cases.

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:103.0) Gecko/20100101 Firefox/103.0

Browser/OS: Firefox 103 on Mac OS X 10.15

View result in a separate tab

Test name	Executions per second
lodash	481645.0 Ops/sec
deepmerge	749370.9 Ops/sec

Related benchmarks:

lodash merge vs deepmerge 4.2.2 (version: 0)

Comparing performance of: lodash vs deepmerge

Created: 2 years ago by: Guest

Jump to the latest result

lodash

deepmerge

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 25 days ago):