Benchmark: lodash.assign vs object.assign vs spread

HTML Preparation code:

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

Tests:

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

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 the provided benchmark and explain what's being tested, compared, and considered.

**What is being tested?**

The benchmark measures the performance difference between three approaches for merging objects:

1. `lodash.assign`
2. `object.assign` (built-in JavaScript method)
3. Spread syntax (`{ ...a, ...b }`)

These approaches are being compared to merge two objects: `a` and `b`. The resulting object is stored in variable `c`.

**Options comparison**

The three options are:

1. **Lodash's `_assign` function**: A popular utility library for functional programming tasks.
2. **Built-in JavaScript method `object.assign`**: A built-in method for merging objects, introduced in ECMAScript 2015 (ES6).
3. **Spread syntax (`{ ...a, ...b }`)**: A shorthand way of creating a new object by spreading the properties of two existing objects.

**Pros and Cons of each approach**

1. **Lodash's `_assign` function**:
	* Pros: Easy to use, well-documented, and widely adopted.
	* Cons: Adds an extra dependency (the Lodash library), and can be slower due to the overhead of function calls.
2. **Built-in JavaScript method `object.assign`**:
	* Pros: Fast, built-in, and doesn't add any extra dependencies.
	* Cons: Requires modern browsers (ES6+), and may have performance differences depending on browser implementations.
3. **Spread syntax (`{ ...a, ...b }`)**:
	* Pros: Fast, concise, and widely supported in modern browsers.
	* Cons: May not be as readable or maintainable for complex merge operations, and can lead to errors if not used correctly.

**Other considerations**

* The benchmark results show that `object.assign` is the fastest approach, followed by spread syntax, and then Lodash's `_assign` function.
* Lodash's `_assign` function may add some overhead due to its own implementation, but it provides more control over merge operations and can be useful in other scenarios.

**Library explanations**

The benchmark uses Lodash version 4.17.5, which is a popular utility library for functional programming tasks.

**Special JS feature or syntax explanation**

There are no special features or syntaxes being tested in this benchmark. The focus is on comparing three established approaches for merging objects.

In summary, the benchmark aims to determine which approach (Lodash's `_assign` function, `object.assign`, or spread syntax) is the fastest and most efficient way to merge two objects.

Latest run results:

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

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:71.0) Gecko/20100101 Firefox/71.0

Browser/OS: Firefox 71 on Linux

View result in a separate tab

Test name	Executions per second
lodash assign	2518996.5 Ops/sec
object.assign	3177520.5 Ops/sec
spread	1555037.6 Ops/sec

Related benchmarks:

lodash.assign vs object.assign vs spread (version: 0)

lodash.merge is NOT equivalent to object.assign, it does much more work so obviously it's slower tbh though lodash.assign is probably just a wrapper for object.assign for all I know

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

Created: 5 years ago by: Guest

Jump to the latest result

lodash assign

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 one month ago):