Benchmark: JavaScript spread operator vs Object.assign performance ( nested )

Tests:

Using the spread operator
const firstObject = { sampleData: 'Hello world', nested: { nestedData: "Worlds" } } const secondObject = { moreData: 'foo bar', oneNest: { secondNest: { nestedData: "Hellos" }} } const finalObject = { ...firstObject, ...secondObject };
Using Object.assign
const firstObject = { sampleData: 'Hello world', nested: { nestedData: "Worlds" } } const secondObject = { moreData: 'foo bar', oneNest: { secondNest: { nestedData: "Hellos" }} } 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

Latest run results:

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

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Let's break down what's being tested in this benchmark.

The benchmark is comparing two approaches to merge two objects in JavaScript: the `...` spread operator and `Object.assign`.

**What are the options being compared?**

1. **Using the spread operator (`...`)**: This syntax allows you to use the spread operator (`...`) to merge two objects by spreading their properties into a new object.
2. **Using `Object.assign()`**: This method takes two or more source objects and merges them into a single target object.

**Pros and Cons of each approach:**

1. **Using the spread operator (`...`)**:
	* Pros:
		+ More concise and readable
		+ Supports merging nested objects
	* Cons:
		+ Only supported in modern browsers (from ES6+)
2. **Using `Object.assign()`**:
	* Pros:
		+ Widespread support across older browsers and Node.js versions
		+ Can be used with function arguments to create a new object
	* Cons:
		+ Less concise than the spread operator syntax
		+ Requires more code to handle nested objects

**Library usage:**

None of the test cases use any external libraries.

**Special JavaScript features or syntax:**

The benchmark uses the `...` spread operator, which is a modern JavaScript feature introduced in ES6. This means that only browsers that support ES6 and later versions will be able to run this benchmark.

**Other alternatives:**

If you don't have access to modern browsers or prefer not to use the spread operator syntax, you can also use `Object.assign()` along with other methods like `JSON.parse(JSON.stringify())` to merge objects. However, keep in mind that this approach may lead to performance issues and is generally less efficient than using the spread operator.

Here's a simple example of how you might use `JSON.parse(JSON.stringify())` to merge objects:
```javascript
const firstObject = { sampleData: 'Hello world', nested: { nestedData: "Worlds" } };
const secondObject = { moreData: 'foo bar', oneNest: { secondNest: { nestedData: "Hellos" }} };

const finalObject = JSON.parse(JSON.stringify(firstObject));
finalObject = Object.assign(finalObject, secondObject);

console.log(finalObject);
```
Keep in mind that this approach can lead to performance issues and is generally less efficient than using the spread operator.

Related benchmarks:

JavaScript spread operator vs Object.assign performance ( nested ) (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):