Benchmark: object-assign-vs-property-assign

Script Preparation code:

function oAssign(o, p){
	return Object.assign(o, p);
}

function pAssign(o, p){
    const y = {};
	for (const k in p) y[k] = p[k];
	return y;
}

Tests:

Object.assign
const o = oAssign({}, {a:1, b:'', c:true});
o.k
const o = pAssign({}, {a:1, b:'', c:true});

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object.assign
o.k

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Firefox/102.0

Browser/OS: Firefox 102 on Linux

View result in a separate tab

Test name	Executions per second
Object.assign	5950761.0 Ops/sec
o.k	11711562.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of MeasureThat.net and explore what's being tested in this benchmark.

**Benchmark Overview**

The benchmark is designed to compare the performance of two approaches for assigning properties to an object: `Object.assign()` (also known as "shallow copy" or "spread syntax") and a custom implementation using the spread operator (`...`). The benchmark aims to measure which approach is faster.

**Options Compared**

Two options are being compared:

1. **`Object.assign()`**: This is a built-in JavaScript function that creates a shallow copy of an object, allowing you to assign properties from another object to the original object.
2. **Custom implementation (`pAssign()`)**: This custom implementation uses a `for...in` loop to iterate over the properties of the source object and assigns each property to a new object using the spread operator (`y[k] = p[k]`). The resulting object is then returned.

**Pros and Cons**

Here's a brief analysis of the pros and cons of each approach:

* **`Object.assign()`**:
	+ Pros: Fast, widely supported, and easy to use.
	+ Cons: May not be suitable for deep copies or objects with circular references.
* **Custom implementation (`pAssign()`)**:
	+ Pros: Can handle more complex scenarios, such as objects with nested properties, but may be slower due to the `for...in` loop.
	+ Cons: Less efficient than `Object.assign()` and may not be suitable for large-scale object assignments.

**Library**

In this benchmark, there is no explicit library mentioned. However, `Object.assign()` is a built-in JavaScript function, which implies that it relies on the V8 engine or other JavaScript engines to execute.

**Special JS Feature/Syntax**

There is no special JavaScript feature or syntax used in this benchmark. The code only utilizes standard JavaScript constructs like objects, properties, and functions.

**Other Alternatives**

If you're looking for alternative approaches to object assignment, some options include:

* Using the spread operator (`...`) directly on the source object: `o = {a: 1, b: '', c: true} {...{a: 2, b: 'b', c: false}};`
* Utilizing a library like Lodash's `assign()` function.
* Implementing a deep copy algorithm using recursive functions or libraries like `json-stringify-safe`.

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

I hope this explanation helps you understand what's being tested in this benchmark!

Related benchmarks:

object-assign-vs-property-assign (version: 0)

Comparing performance of: Object.assign vs o.k

Created: 2 years ago by: Guest

Jump to the latest result

Object.assign

o.k

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):