Benchmark: lodash merge vs object.assign vs spread on empty object

HTML Preparation code:

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

Tests:

lodash merge
var a = { a: 'oh', b: 'my' }; var b = { c: 'goddess' }; var c = _.merge({}, a, b);
object.assign
var a = { a: 'oh', b: 'my' }; var b = { c: 'goddess' }; var c = Object.assign({}, a, b);
spread
var a = { a: 'oh', b: 'my' }; var b = { c: 'goddess' }; var c = { ...a, ...b };

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
lodash merge
object.assign
spread

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 29 days ago):

LLMs can make mistakes. Check important info.

I'd be happy to help you understand the JavaScript microbenchmark on MeasureThat.net.

**Overview**

The benchmark compares three approaches for merging two objects:

1. `_.merge()` from Lodash
2. `Object.assign()`
3. The spread operator (`{ ... }`)

**Options Compared**

* `_._merge()` from Lodash: A utility function that merges two or more objects into one, overriding properties with the same name.
* `Object.assign()`: A built-in JavaScript method that copies the values of all enumerable own properties from one or more source objects to a target object.
* The spread operator (`{ ... }`): A syntax feature in modern JavaScript that allows creating a new object by spreading the properties of an existing object.

**Pros and Cons**

1. `_._merge()` (Lodash):
	* Pros: Fast, efficient, and easy to use. Lodash is a popular utility library, and this function is well-maintained.
	* Cons: Requires importing Lodash, which may slow down the test.
2. `Object.assign()`:
	* Pros: Built-in JavaScript method, fast, and widely supported.
	* Cons: May not be as intuitive or readable as other approaches.
3. Spread operator (`{ ... }`):
	* Pros: Simple, concise, and easy to read.
	* Cons: Only available in modern JavaScript environments (ECMAScript 2018+).

**Library and Syntax**

The benchmark uses the Lodash library for the `_._merge()` function.

Note that the spread operator is a syntax feature introduced in ECMAScript 2018. If you're using an older version of JavaScript, this approach won't work.

**Test Case Breakdown**

Each test case defines a simple scenario:

1. Two objects `a` and `b` with some properties.
2. A new object `c` is created by merging `a` and `b`.

The benchmark measures the execution time for each approach to create `c`. The raw UA string, browser version, device platform, operating system, executions per second, and test name are all provided.

**Other Alternatives**

Other approaches for merging objects could include:

* Using the `Object.create()` method and setting properties.
* Utilizing a custom merge function or algorithm.
* Leveraging other libraries like `merge-deep` or ` deep-merge`.

However, these alternatives are not tested in this specific benchmark.

Latest run results:

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

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/76.0.3809.100 Safari/537.36

Browser/OS: Chrome 76 on Linux

View result in a separate tab

Test name	Executions per second
lodash merge	1201283.0 Ops/sec
object.assign	4399246.5 Ops/sec
spread	18850068.0 Ops/sec

Related benchmarks:

lodash merge vs object.assign vs spread on empty object (version: 0)

Comparing performance of: lodash merge vs object.assign vs spread

Created: 5 years ago by: Guest

Jump to the latest result

lodash merge

object.assign

spread

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 29 days ago):