Benchmark: JavaScript spread operator vs Object.assign performance HDN

Tests:

Using the spread operator
const firstObject = { sampleData: 'Hello world' } const secondObject = { moreData: 'foo bar' } const finalObject = { ...firstObject, ...secondObject };
Using Object.assign
const firstObject = { sampleData: 'Hello world' } const secondObject = { moreData: 'foo bar' } const finalObject = Object.assign({}, firstObject, secondObject);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Using the spread operator
Using Object.assign

Fastest: N/A

Slowest: N/A

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

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Let's break down what is being tested on the provided JSON.

**Benchmark Purpose:**
The benchmark is designed to compare the performance of two ways to merge objects in JavaScript:

1. Using the spread operator (`...`)
2. Using `Object.assign()`

**Options Compared:**

* **Using the spread operator (Object Destructuring)**: This method uses the spread operator (`...`) to create a new object by copying properties from one or more source objects.
	+ Pros:
		- More concise and readable code
		- Less memory allocation, as only the necessary properties are copied
	+ Cons:
		- May have performance overhead due to the creation of a new object
* **Using `Object.assign()`**: This method uses the `Object.assign()` function to merge one or more source objects into a target object.
	+ Pros:
		- Well-established and widely supported library function
		- Can handle complex merging scenarios
	+ Cons:
		- Less concise code compared to the spread operator
		- May have performance overhead due to the creation of a new object

**Library Used:**
In this benchmark, `Object.assign()` is used as the library function. `Object.assign()` is a widely supported and well-established method for merging objects in JavaScript.

**JavaScript Feature/Syntax:**
The test uses the spread operator (`...`) feature, which was introduced in ECMAScript 2018 (ES10). This syntax allows developers to create new objects by copying properties from existing objects using the `...` spread operator.

**Other Considerations:**

* **Memory Allocation:** Both methods have a trade-off between memory allocation and performance. The spread operator may have an advantage here, as it only copies necessary properties.
* **Browser Support:** Since both methods are widely supported, this benchmark is likely relevant to most JavaScript developers.
* **Performance:** This benchmark measures the raw performance of each method, which can be useful for optimizing code in high-performance applications.

**Alternatives:**
Other alternatives for merging objects include:

* **Loose equality operators (`==` or `===`) and conditional statements**: While not recommended due to potential performance overhead and inconsistencies.
* **Array methods (e.g., `concat()`, `slice()`, or `reduce()`) on arrays**: Can be used to merge objects, but may have different performance characteristics than object merging.

Keep in mind that the choice of method depends on the specific use case and requirements. The spread operator is generally preferred for its conciseness and readability, while `Object.assign()` might be a better choice when dealing with complex merging scenarios or legacy codebases.

Related benchmarks:

JavaScript spread operator vs Object.assign performance HDN (version: 0)

Comparing performance of: Using the spread operator vs Using Object.assign

Created: 3 years ago by: Guest

Jump to the latest result

Using the spread operator

Using Object.assign

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

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