Benchmark: JavaScript spread operator vs Object.assign performance 2222

Tests:

Using the spread operator
const firstObject = { sampleData: 'Hello world' } firstObject.moreData = 'foo bar'
Using Object.assign
const firstObject = { sampleData: 'Hello world' } const secondObject = { moreData: 'foo bar' } const finalObject = Object.assign(firstObject, secondObject);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Using the spread operator
Using Object.assign

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 is being tested.

**Benchmark Overview**

The benchmark measures the performance difference between two approaches: using the spread operator (`...`) to merge objects, and using `Object.assign()` to achieve the same result.

**Options Compared**

Two options are compared:

1. **Spread Operator (JavaScript 2015+ syntax)**: This approach uses the spread operator (`...`) to create a new object with the properties of both `firstObject` and `secondObject`. The syntax is `const finalObject = { ...firstObject, ...secondObject };`.
2. **Object.assign() method**: This approach uses the `Object.assign()` method to merge two objects into one. The syntax is `const finalObject = Object.assign(firstObject, secondObject);`.

**Pros and Cons of Each Approach**

* **Spread Operator:**
	+ Pros:
		- More concise and readable syntax.
		- Less boilerplate code required.
		- Can be more efficient in some cases (e.g., when merging objects with only a few properties).
	+ Cons:
		- Not all browsers support the spread operator, so it may not work in older versions of Firefox or other browsers.
		- May have performance overhead due to the creation of a new object.
* **Object.assign():**
	+ Pros:
		- More widely supported across different browsers and versions.
		- Can be more efficient when merging large objects with many properties.
	+ Cons:
		- Less concise syntax compared to the spread operator.
		- Requires additional import statement (`import { Object } from 'object';`) in modern JavaScript environments.

**Other Considerations**

* **Library Usage**: Neither of these approaches uses any external libraries. The `Object.assign()` method is a built-in part of the JavaScript language since ECMAScript 2015 (ES6).
* **Special JS Features/Syntax**: There are no special JavaScript features or syntax used in this benchmark.

**Alternatives**

Other alternatives for merging objects include:

1. Using the `{ ... }` spread operator with an object literal: `const finalObject = { ...firstObject, ...secondObject };`
2. Using a library like Lodash's `merge()` function (if you prefer a more concise syntax).
3. Implementing a custom merge function using recursion or iteration.

Keep in mind that the choice of approach depends on your specific use case and the requirements of your project.

Related benchmarks:

JavaScript spread operator vs Object.assign performance 2222 (version: 0)

Comparing performance of: Using the spread operator vs Using Object.assign

Created: 3 years ago by: Guest

Jump to the latest result

Using the spread operator

Using Object.assign

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):