Benchmark Overview

MeasureThat.net is a website that allows users to create and run JavaScript microbenchmarks. The provided benchmark compares the performance of three different approaches for creating arrays: Array.prototype.concat, the spread operator (...), and the push() method.

Test Cases

There are four test cases:

1. Array.prototype.concat: This test case uses the traditional concat() method to concatenate an array with another array.
2. Spread Operator: This test case uses the spread operator (...) to create a new array by spreading elements from an existing array.
3. jQuery merge: This test case uses the jQuery library's $merge function to concatenate arrays.
4. Push: This test case uses the push() method to add elements to an array and then creates a new array by assigning it to another variable.

Comparison

The comparison is between the performance of these four approaches:

• Array.prototype.concat
• Spread Operator (...)
• jQuery merge
• Push

Options Compared

The options compared are:

• Concatenation methods (traditional concat(), spread operator)
• Array creation methods (push, merge)
• Library usage (jQuery's $merge function)

Pros and Cons

Here are some pros and cons of each approach:

1. Array.prototype.concat

   • Pros: Simple, widely supported, and well-documented.
   • Cons: Can be slow for large arrays due to its iterative nature.

2. Spread Operator (...)

   • Pros: Fast, concise, and modern. It avoids the overhead of creating a new array by concatenating multiple elements.
   • Cons: Requires modern JavaScript versions (ES6+).

3. jQuery merge

   • Pros: Convenient for jQuery developers who are already familiar with its API. However, it may not be as efficient as other methods due to additional overhead from the library.
   • Cons: Adds unnecessary dependency on the jQuery library.

4. Push

   • Pros: Very simple and fast for small arrays or when used correctly (by creating a new array explicitly).
   • Cons: May not be suitable for larger arrays where its performance might degrade due to repeated push() operations, which can lead to frequent reallocations of the underlying array.

Library Usage

In this benchmark, jQuery is used in the "jQuery merge" test case. The $merge function concatenates two arrays and returns a new array containing all elements from both input arrays.

Special JS Feature/Syntax

None of the test cases utilize any special JavaScript features or syntax other than modern ES6+ spread operator (...).