Benchmark: Object.assign vs ES 6 Spread, multiple use cases

Tests:

ES 6 Spread, combining objects
const a = { b: 'c', d: 'e', f: 'g' } const b = { c: 'd', e: 'f', g: 'h' } const c = { ...a, ...b }
Object.assign, combining objects
const a = { b: 'c', d: 'e', f: 'g' } const b = { c: 'd', e: 'f', g: 'h' } const c = Object.assign({}, a, b)
ES 6 Spread, cloning objects
const a = { b: 'c', d: 'e', f: 'g', g: 'h', i: 'j', j: 'k' } const b = { ...a }
Object.assign, cloning objects
const a = { b: 'c', d: 'e', f: 'g', g: 'h', i: 'j', j: 'k' } const b = Object.assign({}, a)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
ES 6 Spread, combining objects
Object.assign, combining objects
ES 6 Spread, cloning objects
Object.assign, cloning objects

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:105.0) Gecko/20100101 Firefox/105.0

Browser/OS: Firefox 105 on Mac OS X 10.15

View result in a separate tab

Test name	Executions per second
ES 6 Spread, combining objects	3817331.0 Ops/sec
Object.assign, combining objects	6096299.0 Ops/sec
ES 6 Spread, cloning objects	6176383.0 Ops/sec
Object.assign, cloning objects	5933585.5 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 benchmark and its test cases.

**Benchmark Purpose:**
The benchmark compares the performance of two approaches for merging or cloning objects in JavaScript:

1. Using the `Object.assign` method with an initial object (i.e., creating a shallow copy).
2. Using the spread operator (`...`) to merge or clone objects.

**Options Compared:**

* **ES 6 Spread**: This approach uses the spread operator to create a new object by merging or cloning existing objects.
* **Object.assign**: This approach uses the `Object.assign` method to merge two objects into a new one, or to create a shallow copy of an object.

**Pros and Cons:**

* **ES 6 Spread**:
	+ Pros: Generally faster, more concise, and easier to read. It also provides a way to merge objects in a single line.
	+ Cons: Not all browsers support the spread operator (see browser compatibility), and it might not work as expected if the objects are very large or complex.
* **Object.assign**:
	+ Pros: Widely supported across most modern browsers, and it's a well-established method for merging objects. It also provides more control over the merge process through options.
	+ Cons: Can be slower than the spread operator in some cases, and it requires multiple lines of code.

**Library Used (if any):**
None explicitly mentioned in this benchmark.

**Special JS Features or Syntax:**
The benchmark uses ES 6 features, specifically:

* The spread operator (`...`)
* Object destructuring (`const b = { ...a }`)

These features are widely supported in modern JavaScript engines and are used to simplify the code and make it more concise.

**Other Alternatives:**
If you're looking for alternative approaches for merging or cloning objects, consider using:

* `JSON.parse(JSON.stringify(obj))`: This method creates a deep copy of an object by serializing it as JSON and then parsing the resulting string back into an object.
* `lodash.merge()`: If you need more complex merge logic or want to handle edge cases, you can use a library like Lodash that provides a robust implementation of merging objects.

However, keep in mind that these alternatives might not be as concise or performant as the ES 6 spread operator and Object.assign methods.

Related benchmarks:

Object.assign vs ES 6 Spread, multiple use cases (version: 0)

Comparing performance of: ES 6 Spread, combining objects vs Object.assign, combining objects vs ES 6 Spread, cloning objects vs Object.assign, cloning objects

Created: 2 years ago by: Guest

Jump to the latest result

ES 6 Spread, combining objects

Object.assign, combining objects

ES 6 Spread, cloning objects

Object.assign, cloning objects

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):