Benchmark: Object.assign() vs Reflect.set()

Tests:

Object.assign()
const obj = {}; Object.assign(obj, {a: {b: 123}});
Reflect.set()
const obj = {}; Reflect.set(obj, 'a', {b: 123});

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object.assign()
Reflect.set()

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 28 days ago)

User agent: Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Mobile Safari/537.36

Browser/OS: Chrome Mobile 131 on Android

View result in a separate tab

Test name	Executions per second
Object.assign()	2716035.2 Ops/sec
Reflect.set()	1659460.5 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.

**What is being tested?**

The benchmark compares the performance of two approaches: `Object.assign()` and `Reflect.set()`. Both methods are used to update the properties of an object in JavaScript.

**Options compared**

Two options are being compared:

1. **`Object.assign()`**: This method takes one or more source objects and merges them into a target object.
2. **`Reflect.set()`**: This is a static method on the `Reflect` object that sets the value of a property directly on an object.

**Pros and cons**

* **`Object.assign()`**:
	+ Pros: widely supported, easy to use, can be used with multiple sources in a single call.
	+ Cons: may incur overhead due to the creation of a new array when using multiple sources.
* **`Reflect.set()`**:
	+ Pros: provides more control over property updates, does not create a new array.
	+ Cons: not as widely supported (only available since ECMAScript 2018), requires importing the `Reflect` object.

**Other considerations**

When choosing between these two methods, consider the following:

* If you need to update multiple properties at once and don't mind creating a new array, `Object.assign()` might be sufficient.
* If you need more control over individual property updates or want to avoid creating a new array, `Reflect.set()` is a better choice.

**Library**

There are no libraries mentioned in the benchmark definition. However, note that some older browsers may not support `Reflect.set()`, so it's always a good idea to include fallbacks or polyfills when using this method.

**Special JS feature/syntax**

No special JavaScript features or syntax are being used in this benchmark.

**Benchmark preparation code and HTML Preparation Code**

The benchmark definition only provides script preparation code (`Object.assign()` vs `Reflect.set()`) and no HTML preparation code is specified. This suggests that the benchmark is focused solely on measuring the performance of these two methods.

**Other alternatives**

If you need to measure other approaches for updating object properties, some alternatives include:

* Using the ` bracket notation` (e.g., `obj['a'] = {b: 123}`) or the ` in-operator` (e.g., `if ('a' in obj) { obj.a = {b: 123}; }`)
* Using a library like Lodash's `setIn()` function
* Using a library like Immutable.js for immutable objects

However, without more information about your specific use case, it's difficult to recommend the best alternative approach.

Related benchmarks:

Object.assign() vs Reflect.set() (version: 0)

Comparing performance of: Object.assign() vs Reflect.set()

Created: 3 years ago by: Guest

Jump to the latest result

Object.assign()

Reflect.set()

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):