Benchmark: JavaScript spread operator vs Object.assign performance 1_1

Tests:

Using the spread operator
const firstObject = { sampleData: 'Hello world' + Math.random(), moreData: 'here we go' + Math.random() } const secondObject = { sampleData: 'foo bar' + Math.random(), moreData: 'here we go2' + Math.random() } const finalObject = { ...firstObject, ...secondObject };
Using Object.assign
const firstObject = { sampleData: 'Hello world' + Math.random(), moreData: 'here we go' + Math.random() } const secondObject = { sampleData: 'foo bar' + Math.random(), moreData: 'here we go2' + Math.random() } 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:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/119.0.0.0 Safari/537.36

Browser/OS: Chrome 119 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Using the spread operator	1508808.5 Ops/sec
Using Object.assign	1423379.8 Ops/sec

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

LLMs can make mistakes. Check important info.

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

**Benchmark Purpose:**
The benchmark is designed to compare the performance of two approaches: using the spread operator (`...`) in JavaScript and using `Object.assign()` to merge two objects.

**Options Compared:**

1. **Using the Spread Operator (`...`)**:
	* This approach creates a new object by spreading the properties of the `firstObject` and `secondObject` into it.
	* The syntax is more concise and modern, but may be less readable for some developers.
	* Pros:
		+ Concise syntax
		+ Modern and expressive
	* Cons:
		+ May not work as expected in older browsers or environments that don't support the spread operator
2. **Using `Object.assign()`**:
	* This approach merges two objects using a shallow assignment.
	* The syntax is more traditional, but may be less readable for some developers.

**Pros and Cons:**

* Using the Spread Operator (`...`):
	+ Pros: concise syntax, modern, expressive
	+ Cons: may not work in older browsers or environments
* Using `Object.assign()`:
	+ Pros: widely supported, traditional syntax
	+ Cons: less readable for some developers

**Library and Syntax Used:**
The benchmark uses the JavaScript spread operator (`...`) and `Object.assign()` methods. No external libraries are required.

**Special JS Features/Syntax Used:**
The benchmark uses the spread operator (`...`), which is a modern JavaScript feature that was introduced in ECMAScript 2018 (ES2018). This syntax allows for concise object creation and merging.

**Other Alternatives:**
If you prefer not to use the spread operator or `Object.assign()`, other alternatives include:

1. Using a library like Lodash, which provides a `merge()` function that can be used to merge objects.
2. Using a traditional loop to iterate over the properties of one object and assign them to another.
3. Using JSON merge patches (e.g., Ramda's `merge` function) to merge objects.

However, keep in mind that these alternatives may have different performance characteristics or syntax trade-offs compared to using the spread operator or `Object.assign()`.

Related benchmarks:

JavaScript spread operator vs Object.assign performance 1_1 (version: 0)

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

Created: one year ago by: Guest

Jump to the latest result

Using the spread operator

Using Object.assign

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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