Benchmark: lodash merge vs object.assign vs spread vs manual forEach for array merging

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' }, { c: 'goddess' }, { a: 'anime'}, { b: 'is', c: 'cool' } ]; var c = {}; _.forEach(a, (val, key) => { _.merge(c, {key: val}); });
object.assign
var a = [ { a: 'oh', b: 'my' }, { c: 'goddess' }, { a: 'anime'}, { b: 'is', c: 'cool' } ]; var c = {}; _.forEach(a, (val, key) => { Object.assign(c, {key: val}); });
spread
var a = [ { a: 'oh', b: 'my' }, { c: 'goddess' }, { a: 'anime'}, { b: 'is', c: 'cool' } ]; var c = {}; _.forEach(a, (val, key) => { c = {...c, key: val}; });
Manual forEach
var a = [ { a: 'oh', b: 'my' }, { c: 'goddess' }, { a: 'anime'}, { b: 'is', c: 'cool' } ]; var c = {}; _.forEach(a, (val, key) => { c[key] = val; });

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
lodash merge
object.assign
spread
Manual forEach

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 JSON and benchmark information to understand what is being tested.

**Benchmark Overview**

The benchmark tests four different approaches for merging an array of objects into a single object:

1. `lodash merge`
2. `object.assign`
3. `spread` (using the spread operator)
4. `Manual forEach`

Each approach has its own pros and cons, which we'll discuss below.

**Options Compared**

Here's a brief summary of each option:

* **_lodash merge`:** Uses the Lodash library to perform deep object merging. This approach is often used when working with complex data structures.
	+ Pros: Efficient, handles nested objects, and provides a robust implementation.
	+ Cons: Requires an external library (Lodash), can be slower due to overhead.
* **`object.assign`:** Uses the `assign` method of the Object prototype to merge properties. This approach is simple and straightforward but may not handle nested objects as efficiently.
	+ Pros: Lightweight, easy to implement, and suitable for simple cases.
	+ Cons: May not work well with complex data structures, can be slower due to recursive calls.
* **`spread`:** Uses the spread operator (`{...obj}`) to create a new object by copying properties from an existing object. This approach is concise but may not handle nested objects or arrays efficiently.
	+ Pros: Concise, easy to implement, and suitable for simple cases.
	+ Cons: May not work well with complex data structures, can be slower due to recursive calls.
* **`Manual forEach`:** Uses a `forEach` loop to iterate over the array and assign values to the target object. This approach is low-level and may require more effort to implement correctly.
	+ Pros: Allows for fine-grained control, no external libraries required.
	+ Cons: Can be slower due to manual looping, more prone to errors.

**Other Considerations**

When choosing an approach, consider the following factors:

* Complexity of data structures: If you're working with complex nested objects or arrays, `lodash merge` might be a better choice. For simpler cases, `object.assign`, `spread`, or `Manual forEach` might suffice.
* Performance: If speed is critical, `object.assign` and `spread` are often faster due to their lightweight nature. However, the impact on performance may vary depending on the specific use case.
* Readability and maintainability: Choose an approach that balances conciseness with clarity and readability.

**Lodash Library**

The Lodash library provides a robust implementation of object merging, including support for deep objects and arrays. It's often used in data processing and manipulation tasks where efficiency is crucial.

**Chrome 102 Browser Details**

The provided benchmark results indicate that Chrome 102 is running on a Macintosh (Mac OS X 10.15.7) desktop platform. The average execution rate per second varies between the four approaches, with `spread` being the fastest followed by `Manual forEach`.

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/102.0.5005.40 Safari/537.36

Browser/OS: Chrome 102 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
lodash merge	217117.1 Ops/sec
object.assign	1141389.6 Ops/sec
spread	3709379.2 Ops/sec
Manual forEach	2748031.0 Ops/sec

Related benchmarks:

lodash merge vs object.assign vs spread vs manual forEach for array merging (version: 0)

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

Created: 4 years ago by: Guest

Jump to the latest result

lodash merge

object.assign

spread

Manual forEach

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):