Benchmark: property access: object with define property vs Proxy get

Script Preparation code:

const queryResults = {
  a: {},
  b: [2, 3, 4],
  c: 3,
  d: {
    a: 1,
    b: [],
  },
};

window.trackedResultsProxy = new Proxy(queryResults, {
  get(target, prop, receiver) {
    return Reflect.get(target, prop, receiver);
  }
});

window.trackedResultsDefineProperty = {};
for (const key of Object.keys(queryResults)) {
  Object.defineProperty(trackedResultsDefineProperty, key, {
    configurable: false,
    enumerable: true,
    get() {
      return queryResults[key];
    },
  });
}

window.trackedResultsGetter = {
  get d() {
    return queryResults.d;
  }
}

Tests:

Proxy
window.trackedResultsProxy.d.a + 5
defineProperty
window.trackedResultsDefineProperty.d.a + 5
getter
window.trackedResultsGetter.d.a + 5

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Proxy
defineProperty
getter

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 4 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:128.0) Gecko/20100101 Firefox/128.0

Browser/OS: Firefox 128 on Windows

View result in a separate tab

Test name	Executions per second
Proxy	4833679.5 Ops/sec
defineProperty	5918428.5 Ops/sec
getter	5462940.5 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark definition and test cases.

**Benchmark Definition:**
The benchmark measures the performance of accessing a property with different approaches:

1. `window.trackedResultsProxy`: A Proxy object, which is a special type of object that allows you to intercept and modify access to its properties.
2. `window.trackedResultsDefineProperty`: An object created using `Object.defineProperty()`, which defines a property on an object.
3. `window.trackedResultsGetter`: An object with a getter property that returns the value of another property.

**Options Compared:**

* **Proxy**: The Proxy object is used to intercept and modify access to its properties. When you access a property on the Proxy object, it calls the `get()` method specified in the Proxy's `get()` trap.
* **defineProperty**: The `Object.defineProperty()` method creates a new property on an object. In this case, a property named "d" is created on `window.trackedResultsDefineProperty` with a getter function that returns the value of another property.
* **Getter**: The `window.trackedResultsGetter` object has a getter property named "d" that returns the value of another property.

**Pros and Cons:**

* **Proxy**:
	+ Pros:
		- Can be used to intercept and modify access to properties at runtime.
		- Can provide more flexibility and customization than `defineProperty`.
	+ Cons:
		- May have performance overhead due to the additional indirection.
* **defineProperty**:
	+ Pros:
		- Creates a new property on an object that is faster than creating it dynamically using a Proxy.
		- Less complex than using a Proxy.
	+ Cons:
		- Less flexible and customizable than using a Proxy.
* **Getter**:
	+ Pros:
		- Is a simple way to expose a value from another object.
	+ Cons:
		- Does not provide any flexibility or customization options.

**Library Usage:**
The `Reflect` library is used in the `get()` trap of the Proxy object. It provides functions for working with objects, such as `Reflect.get()`, which returns the value of a property on an object.

**Special JavaScript Feature/Syntax:**
The use of the `Proxy` object and its `get()` trap introduces some advanced JavaScript concepts:

* **Prototypal Inheritance**: The Proxy object inherits from the native Object prototype.
* **Property Traps**: The `get()` trap allows you to intercept and modify access to properties on an object.

**Other Alternatives:**

* Instead of using a Proxy, you could use a plain object and define getters and setters manually.
* You could use the `Object.create()` method to create an object that inherits from another object.
* You could use a library like Lodash or Ramda to provide more flexible and customizable ways to work with objects.

In summary, the benchmark measures the performance of accessing a property using different approaches: Proxy, defineProperty, and Getter. The Proxy approach provides flexibility and customization options but may have performance overhead, while defineProperty is faster but less flexible.

Related benchmarks:

property access: object with define property vs Proxy get (version: 0)

Comparing performance of: Proxy vs defineProperty vs getter

Created: one year ago by: Guest

Jump to the latest result

Proxy

defineProperty

getter

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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