Benchmark: spread- concat-unshift-twa-arrays

Script Preparation code:

const array = [1, 2, 3];
const array2 = [4, 5];

Tests:

arrayUnshift
const array = [1, 2, 3]; const array2 = [4, 5]; array.unshift(...array2);
arrayConcat
let array = [1, 2, 3]; const array2 = [4, 5]; array = array.concat(array2)
arraySpread
let array = [1, 2, 3]; const array2 = [4, 5]; array = [...array, ...array2]

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
arrayUnshift
arrayConcat
arraySpread

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 6 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/142.0.0.0 Safari/537.36

Browser/OS: Chrome 142 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
arrayUnshift	22699142.0 Ops/sec
arrayConcat	16306900.0 Ops/sec
arraySpread	43239244.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Measuring the performance of JavaScript operations can be complex, but I'll break it down for you.

**Benchmark Definition:**

The benchmark definition is a JSON object that contains information about the test case. In this case, there are three test cases:

* `spread- concat-unshift-twa-arrays`: This is the name of the benchmark, which describes what's being tested.
* `Script Preparation Code` and `Html Preparation Code`: These fields contain JavaScript code that needs to be executed before running the test case. In this case, both are empty, indicating a simple benchmark.

**Individual Test Cases:**

Each test case represents a specific operation on arrays:

1. **arrayUnshift**: This test case checks how fast `unshift()` can modify an array by spreading another array into it.
	* The JavaScript code `const array = [1, 2, 3]; const array2 = [4, 5]; array.unshift(...array2);` creates two arrays and then uses the spread operator (`...`) to add all elements from `array2` to `array`, followed by a direct call to `unshift()`.
	* The purpose of this test is likely to compare the performance of different ways to modify an array, such as using `push()` or `unshift()`.
2. **arrayConcat**: This test case checks how fast `concat()` can modify an array by spreading another array into it.
	* The JavaScript code `let array = [1, 2, 3]; const array2 = [4, 5]; array = array.concat(array2)` creates two arrays and then uses the spread operator (`...`) to add all elements from `array2` to `array`, followed by a direct call to `concat()`.
	* Similar to `arrayUnshift`, this test is likely comparing different ways to modify an array.
3. **arraySpread**: This test case checks how fast using the spread operator (`...`) can create a new array by spreading elements from another array.

**Library:**

None of these test cases seem to use any specific library, but `concat()` and `unshift()` are built-in methods in JavaScript. However, if you're using older browsers or environments that don't support modern JavaScript features, some libraries might be used as workarounds (e.g., polyfills).

**Special JS Features:**

None of these test cases use any special JavaScript features, such as async/await, generators, or classes.

**Pros and Cons:**

* **Using `unshift()` vs. spread operator (`...`)**:
	+ Using `unshift()` can be faster because it modifies the array in-place without creating a new one.
	+ However, using the spread operator (`...`) is generally more readable and flexible when working with arrays.
* **Using `concat()` vs. spread operator (`...`)**:
	+ Like with `unshift()`, using `concat()` can be faster because it modifies the array in-place without creating a new one.
	+ However, using the spread operator (`...`) is generally more concise and readable when working with arrays.

**Other Alternatives:**

* Instead of using `push()` to add elements to an array, you could use `unshift()` or the spread operator (`...`).
* If you want to create a new array without modifying the original one, you could use the spread operator (`...`) or the `slice()` method.
* For larger arrays, using `Array.prototype.slice()` can be more efficient than creating a new array with the spread operator (`...`).

In general, when working with arrays in JavaScript, it's essential to consider performance and readability. The choice of operation depends on the specific use case and your personal preference.

Related benchmarks:

spread- concat-unshift-twa-arrays (version: 0)

spread- concat-unshift-twa-arrays

Comparing performance of: arrayUnshift vs arrayConcat vs arraySpread

Created: 2 years ago by: Guest

Jump to the latest result

arrayUnshift

arrayConcat

arraySpread

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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