Benchmark: Object.defineProperty vs assignment

Script Preparation code:

window.A = class A {
    constructor () {
      Object.defineProperty(this, 'a', {value: 'a'})
    }
}

window.B = class B {
    constructor () {
      this.a = 'a'
    }
}

Tests:

defineProperty
new A()
assignment
new B()

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
defineProperty
assignment

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/96.0.4664.110 Safari/537.36

Browser/OS: Chrome 96 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
defineProperty	2272125.5 Ops/sec
assignment	8055535.0 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):

LLMs can make mistakes. Check important info.

**Benchmark Overview**

The provided JSON represents a JavaScript benchmark test case on MeasureThat.net, which compares the performance of two approaches: using `Object.defineProperty` and assigning properties directly to an object.

**Script Preparation Code**

The script preparation code defines two classes, `A` and `B`, which are used as test subjects. Class `A` uses `Object.defineProperty` to define a property named "a" with value "a", while class `B` simply assigns the string "a" directly to its `a` property.

**Comparison Options**

The benchmark compares two options:

1. **Using `Object.defineProperty` (Class A)**: This approach defines properties on an object using the `Object.defineProperty()` method. This method allows for more control over property definitions, such as specifying access modifiers and validation.
2. **Assigning properties directly (Class B)**: This approach assigns values to an object's properties directly, without using a specific method.

**Pros and Cons**

* Using `Object.defineProperty`:
	+ Pros:
		- Provides more control over property definitions.
		- Can help with code organization and maintainability.
	+ Cons:
		- May be slower due to the additional overhead of method calls.
* Assigning properties directly:
	+ Pros:
		- Faster, as it avoids the overhead of method calls.
	+ Cons:
		- Less control over property definitions.

**Library Usage**

None of the test cases use any external libraries. The script preparation code is self-contained and relies only on built-in JavaScript features.

**Special JS Features or Syntax**

There are no special JavaScript features or syntax used in this benchmark. It's a simple, straightforward comparison between two approaches to defining properties on an object.

**Alternative Approaches**

Other approaches to defining properties on an object might include:

1. Using getters and setters: This approach provides more control over property definitions, but may be slower due to the additional overhead of method calls.
2. Using a factory function or constructor with a `this` parameter: This approach can provide a way to create objects with default properties, but may not offer as much control as using `Object.defineProperty`.
3. Using a library like Lodash or Underscore.js to handle property definitions: These libraries often provide more concise and expressive ways to define properties, but may come with additional dependencies and overhead.

In conclusion, this benchmark provides a simple and straightforward comparison between two approaches to defining properties on an object. The results can help developers understand the performance implications of using `Object.defineProperty` versus assigning properties directly.

Related benchmarks:

Object.defineProperty vs assignment (version: 0)

Comparing performance of: defineProperty vs assignment

Created: 3 years ago by: Guest

Jump to the latest result

defineProperty

assignment

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):