Benchmark: Object.assign Spread vs Object.assign.apply 3

HTML Preparation code:

<script>

const batch = [
  { foo: 'foo' },
  { bar: 'bar' },
  { baz: 'baz' }
]

const spread = (target, batch) => {
  for (let i = 0; i < batch.length; i++) {
    Object.assign(target, batch[i])
  }
}

const test1 = () => Object.assign({}, ...batch)
const test2 = () => Object.assign.apply(Object, batch)
const test3 = () => spread({}, batch)

</script>

Tests:

Object.assign Spread
test1()
Object.assign.apply
test2()
Spread Function
test3()

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object.assign Spread
Object.assign.apply
Spread Function

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4389.128 Safari/537.36 Edg/89.0.774.77

Browser/OS: Chrome 89 on Windows

View result in a separate tab

Test name	Executions per second
Object.assign Spread	2629079.2 Ops/sec
Object.assign.apply	7069158.5 Ops/sec
Spread Function	4998658.5 Ops/sec

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

LLMs can make mistakes. Check important info.

**Benchmark Explanation**

The provided JSON represents a JavaScript benchmark test case that compares the performance of three different approaches to merge an array into an object using the `Object.assign` method or its variants.

**Options Compared:**

1. **`Object.assign` with spread operator (`...`)**: This approach uses the spread operator to create a new array and then passes it to `Object.assign`.
2. **`Object.assign.apply`**: This approach uses the `apply` method to pass an array as the first argument to `Object.assign`.
3. **Spread function (custom implementation)**: This approach defines a custom function (`spread`) that merges an object with an array of objects using `Object.assign`.

**Pros and Cons of Each Approach:**

1. **`Object.assign` with spread operator (`...`)**:
	* Pros:
		+ Concise and readable syntax
		+ Well-supported by modern browsers
	* Cons:
		+ Can be slower due to the creation of a new array
2. **`Object.assign.apply`**:
	* Pros:
		+ Allows for fine-grained control over the merging process
	* Cons:
		+ Less readable syntax compared to spread operator
		+ May not be supported by older browsers
3. **Spread function (custom implementation)**:
	* Pros:
		+ Can be optimized for performance
	* Cons:
		+ More complex and less readable syntax compared to spread operator

**Library and Purpose:**

There is no explicit library mentioned in the provided JSON, but it's likely that `Object.assign` is a built-in JavaScript method.

**Special JS Feature or Syntax:**

The spread operator (`...`) is a relatively new feature introduced in ECMAScript 2015 (ES6). It allows for concise syntax when merging objects or arrays. The custom `spread` function implementation uses this syntax, but it's not a specific feature that requires special knowledge.

**Other Considerations:**

When implementing benchmarks like this one, consider the following:

* **Test setup and teardown**: Make sure to clean up any side effects of the benchmark tests.
* **Consistency**: Ensure that all test cases have consistent input data and conditions.
* **Repeatibility**: Run multiple iterations of each test case to ensure accurate results.

**Alternative Approaches:**

If you're interested in exploring alternative approaches, consider using:

* **Lodash's `merge` function**: A popular utility library that provides a robust implementation for merging objects.
* **Underscore.js's `_extend` function**: Another popular utility library that offers a comprehensive solution for merging objects.

Keep in mind that these alternatives might introduce additional dependencies and complexity.

Related benchmarks:

Object.assign Spread vs Object.assign.apply 3 (version: 0)

Comparing performance of: Object.assign Spread vs Object.assign.apply vs Spread Function

Created: 3 years ago by: Guest

Jump to the latest result

Object.assign Spread

Object.assign.apply

Spread Function

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):