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
};

AخA
 
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);

 
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

Experimental features:

Memory measurements supported only in Chrome.
For precise memory measurements Chrome must be launched with --enable-precise-memory-info flag.
More information: Monitoring JavaScript Memory

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 7 months ago):

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:

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
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:

Using a library like Lodash, which provides a merge() function that can be used to merge objects.
Using a traditional loop to iterate over the properties of one object and assign them to another.
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().

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

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