Benchmark: Array push vs spread operator (including front)

Tests:

Push
var params = [ "hello", true, 7 ] var other = params.push(1);
Spread
var params = [ "hello", true, 7 ] var other = [...params, 1];
Push Front
var params = [ "hello", true, 7 ] var other = params.unshift(1);
Spread Front
var params = [ "hello", true, 7 ] var other = [1, ...params];

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Push
Spread
Push Front
Spread Front

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 5 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/81.0.4044.92 Safari/537.36

Browser/OS: Chrome 81 on Mac OS X 10.14.3

View result in a separate tab

Test name	Executions per second
Push	18147846.0 Ops/sec
Spread	11412336.0 Ops/sec
Push Front	6267919.5 Ops/sec
Spread Front	20466118.0 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what's being tested, compared, and their pros and cons.

**Benchmark Definition**

The benchmark compares different methods for adding elements to an array in JavaScript:

1. `Array.push()`: The traditional method of pushing an element onto the end of an array.
2. The new ES6 spread operator (`...`): A shorthand way of creating a new array by copying all elements from an existing array and adding one or more additional elements.

**Test Cases**

There are four test cases, each comparing a different approach:

1. **Push**: Uses `Array.push()` to add an element to the end of the array.
2. **Spread**: Uses the spread operator (`...`) to create a new array by copying all elements from the original array and adding one or more additional elements.
3. **Push Front**: Uses `Array.unshift()` to add an element to the beginning of the array.
4. **Spread Front**: Uses the spread operator (`...`) to create a new array by copying all elements from the original array and adding one or more additional elements at the beginning.

**Pros and Cons**

Here's a brief summary of the pros and cons of each approach:

* `Array.push()`:
	+ Pros: Simple, widely supported, and easy to understand.
	+ Cons: Can be slower than other methods, especially for large arrays, since it involves allocating new memory and updating internal array indices.
* The spread operator (`...`):
	+ Pros: Concise, efficient, and can reduce code duplication. It also provides a clear and intuitive way of creating a new array by copying existing elements.
	+ Cons: May be slower than other methods for very large arrays due to the overhead of creating a new array object. Additionally, it requires support for ES6 syntax, which may not be available in older browsers or environments.

**Library and Special JS Feature**

None of the test cases rely on any external libraries or special JavaScript features beyond what's considered standard for modern browsers (e.g., no Web Workers, async/await, etc.).

**Other Alternatives**

Some alternative methods for adding elements to an array include:

* Using `Array.prototype.concat()` instead of `push()`: This creates a new array and returns it.
* Using `Array.prototype.splice()` instead of `push()`: This modifies the original array in place.
* Using a `for` loop or other iteration constructs to add elements one by one.

These alternatives may have their own pros and cons, depending on the specific use case and performance requirements.

Related benchmarks:

Array push vs spread operator (including front) (version: 0)

Compare the new ES6 spread operator with the traditional push method

Comparing performance of: Push vs Spread vs Push Front vs Spread Front

Created: 5 years ago by: Guest

Jump to the latest result

Push

Spread

Push Front

Spread Front

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):