Benchmark: includes/push vs spread

Tests:

includes/push
const a1 = [0,1,2,3,4,5,6,7,8,9]; const a2 = 10; if (!a1.includes(a2)) a1.push(a2);
spread
let b1 = [0,1,2,3,4,5,6,7,8,9]; const b2 = 10; b1 = [...b1, b2]

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
includes/push
spread

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/111.0.0.0 Safari/537.36

Browser/OS: Chrome 111 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
includes/push	47671600.0 Ops/sec
spread	48616252.0 Ops/sec

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

LLMs can make mistakes. Check important info.

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

**Benchmark Overview**

The benchmark is designed to compare two approaches for adding an element to an array in JavaScript:

1. Using `includes()` method with push()
2. Using spread syntax (`...`)

**Options Compared**

The benchmark compares two options:

a) **Using `includes()` method with push()**: This approach checks if the element exists in the array using the `includes()` method and then adds it to the end of the array using the `push()` method.

b) **Using spread syntax (`...`)**: This approach uses the spread operator (`...`) to create a new array with the existing elements and the new element, instead of modifying the original array.

**Pros and Cons**

Here are some pros and cons of each approach:

a) **Using `includes()` method with push()**:
	+ Pros: Simple and straightforward implementation. Works well for small arrays.
	+ Cons: May be slower for large arrays due to the overhead of checking if an element exists in the array using `includes()`.
	+ Additional overhead: The `push()` method can shift all elements after the insertion point, which may not be desirable in some cases.

b) **Using spread syntax (`...`)**:
	+ Pros: More efficient and concise implementation. Works well for large arrays.
	+ Cons: May have higher memory overhead due to creating a new array. Can also lead to unexpected behavior if not used carefully.

**Library Usage**

There is no explicit library usage in the benchmark. However, it's worth noting that some JavaScript engines may optimize certain features or functions (like `includes()`), which could affect the benchmark results.

**Special JS Features/Syntax**

The benchmark uses a special feature: the spread syntax (`...`). This is a relatively recent addition to JavaScript and was introduced in ECMAScript 2015 (ES6). It allows creating new arrays from existing iterables, such as arrays or objects, using the `...` operator.

**Other Alternatives**

If you were to rewrite this benchmark, you might consider alternative approaches, such as:

* Using `Array.prototype.push.apply()` instead of `push()`: This can be more efficient for large arrays.
* Using `at()` method instead of `includes()`: This is a more modern and efficient way to check if an element exists in an array.
* Using iterative approach instead of spread syntax: You could use a loop to iterate over the elements of the original array and add the new element, which might be more predictable and memory-efficient.

Keep in mind that these alternatives may not provide significant performance benefits for small arrays or simple operations.

Related benchmarks:

includes/push vs spread (version: 0)

Comparing performance of: includes/push vs spread

Created: one year ago by: Guest

Jump to the latest result

includes/push

spread

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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