Benchmark: lodash merge vs object.assign vs spread (no intermediate vars)

HTML Preparation code:

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

Tests:

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

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

Latest run results:

Run details: (Test run date: 4 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4186.0 Safari/537.36

Browser/OS: Chrome 86 on Mac OS X 10.15.5

View result in a separate tab

Test name	Executions per second
lodash merge	2647033.8 Ops/sec
object.assign	5045269.5 Ops/sec
spread	1758505.4 Ops/sec

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

LLMs can make mistakes. Check important info.

**What is being tested?**

The provided JSON represents a benchmark test that compares the performance of three different approaches to merge two objects in JavaScript: `lodash.merge`, `Object.assign`, and the spread operator (`...`). The test case uses no intermediate variables.

**Options comparison**

Here's a brief overview of each approach, their pros and cons:

1. **Lodash Merge**: Lodash is a popular utility library that provides various functions for tasks like array manipulation, object merging, and more. `lodash.merge` takes two objects as input and returns a new object containing the merged properties.
	* Pros: Efficient, flexible, and well-maintained.
	* Cons: Requires an additional library, can be slower due to the overhead of importing it.
2. **Object.assign**: This is a built-in JavaScript method that copies properties from one or more source objects to a target object.
	* Pros: Fast, efficient, and part of the standard library.
	* Cons: Only works with objects, not arrays or other data types.
3. **Spread Operator (`...`)**: Introduced in ECMAScript 2015, the spread operator allows you to expand an array-like object into individual arguments.
	* Pros: Simple, concise, and part of the standard library.
	* Cons: Only works with objects, not arrays or other data types.

**Library usage**

The test uses the `lodash` library for the `lodash.merge` approach. Lodash is a popular utility library that provides various functions for tasks like array manipulation, object merging, and more. It's widely used in JavaScript applications due to its extensive feature set and efficient implementation.

**Special JS features or syntax**

There are no special JavaScript features or syntaxes used in this benchmark test. All three approaches use standard JavaScript constructs.

**Other alternatives**

If `lodash` is not an option, other alternatives for merging objects include:

* Using the `Object.assign()` method with a third argument to specify the target object.
* Implementing your own custom merge function using `for...in`, `Object.keys()`, and other built-in methods.
* Utilizing a different library, such as `underscore.js` or `ramda`.

However, it's worth noting that these alternatives might not be as efficient or concise as `lodash.merge` or the spread operator.

**Benchmark interpretation**

The benchmark results show the execution time (in executions per second) for each test case on a Chrome 86 browser running on Mac OS X 10.15.5. The top performer is `Object.assign`, followed by the spread operator, and then `lodash.merge`.

Related benchmarks:

lodash merge vs object.assign vs spread (no intermediate vars) (version: 0)

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

Created: 4 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 2 months ago):