Benchmark: merge vs object.assign vs spread1

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', d: 'ss' }; var b = { c: 'goddess', d: 's2s' }; var c = _.merge(a, b); console.log(c)
object.assign
var a = { a: 'oh', b: 'my', d: 'ss' }; var b = { c: 'goddess', d: 's2s' }; var c = Object.assign(a, b); console.log(c)
spread
var a = { a: 'oh', b: 'my', d: 'ss' }; var b = { c: 'goddess', d: 's2s' }; var c = { ...a, ...b }; console.log(c)

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

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

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

**Benchmark Overview**

The benchmark compares three approaches to merge two objects: `_.merge` from Lodash, `Object.assign`, and the spread operator (`...`). The test creates two objects, `a` and `b`, with some common properties. It then merges these objects using each of the three approaches and logs the resulting object to the console.

**Options Compared**

1. **Lodash merge**: This approach uses Lodash's `merge` function to combine the properties of `a` and `b`. Lodash is a utility library that provides various functions for tasks like array manipulation, string formatting, and object merging.
2. **Object.assign**: This approach uses the `Object.assign` method to create a new object with the properties of `a` and `b`. Object assign is a built-in JavaScript function that merges one or more source objects into a target object.
3. **Spread operator (`...`)**: This approach uses the spread operator to merge the properties of `a` and `b`. The spread operator creates a new object by spreading the properties of an existing object.

**Pros and Cons**

1. **Lodash merge**: Pros:
	* Provides more control over the merging process, as you can specify options like `deep: true` or `compatibilityMode`.
	* Handles complex cases like array merging and circular references.
	* Can be faster for large objects due to its optimized implementation.

Cons:
	* Requires Lodash to be loaded, which may add extra weight to your application.
	* Has a higher learning curve compared to other methods.
2. **Object.assign**: Pros:
	* Built-in function, so it doesn't require any additional libraries.
	* Fast and efficient for simple object merges.
	* Supports most modern browsers.

Cons:
	* Can be slower for large objects due to the overhead of creating a new object.
	* May not handle complex cases like array merging or circular references correctly.
3. **Spread operator (`...`)**: Pros:
	* Fast and efficient, as it creates a new object with minimal overhead.
	* Handles most simple case merging scenarios.
	* Part of modern JavaScript, so no additional libraries are needed.

Cons:
	* Limited control over the merging process.
	* May not work correctly for complex cases like array merging or circular references.
	* Can lead to unexpected behavior if not used carefully.

**Additional Considerations**

1. **Performance**: The spread operator is generally the fastest approach, followed closely by `Object.assign`, and then Lodash's `merge`.
2. **Compatibility**: Make sure to test each approach in multiple browsers and environments to ensure compatibility.
3. **Code readability**: Choose the approach that best fits your codebase's style and conventions.

**Other Alternatives**

1. **JSON merge**: Some implementations, like JSON Merge Patch (JMP), can be used for more complex object merging scenarios.
2. **Function compositions**: In some cases, function composition techniques like using `Object.keys()` or `for...in` loops can provide more control over the merging process.

In summary, the benchmark compares three approaches to merge objects: Lodash's `merge`, `Object.assign`, and the spread operator (`...`). The choice of approach depends on factors like performance, compatibility, code readability, and the specific requirements of your project.

Related benchmarks:

merge vs object.assign vs spread1 (version: 0)

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

Created: 3 years ago by: Guest

Jump to the latest result

lodash merge

object.assign

spread

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

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