Benchmark: Push vs spread vs copy and push, for appending single item

Tests:

Push
var arr = ["This", "is", "an", "array", "of", "strings", "which", "might", "be", "copied"]; arr.push("foo");
Spread
var arr = ["This", "is", "an", "array", "of", "strings", "which", "might", "be", "copied"]; arr = [...arr, "foo"];
Copy and push
var arr = ["This", "is", "an", "array", "of", "strings", "which", "might", "be", "copied"]; arr = arr.slice(); arr.push("foo");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Push
Spread
Copy and push

Fastest: N/A

Slowest: N/A

Latest run results:

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

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Let's break down the provided JSON and benchmark results to understand what is being tested.

**Benchmark Definition**

The benchmark definition is not explicitly explained, but based on the test cases, it appears that the goal is to compare the performance of three different approaches for appending a single item to an array:

1. `Push`: Using the `push()` method to add an item to the end of the array.
2. `Spread`: Using the spread operator (`...`) to create a new array and then adding the item to it, assigning the result back to the original array.
3. `Copy and push`: Using the `slice()` method to create a shallow copy of the array, modifying the copied array with `push()`, and then pushing the item to the end of the original array.

**Options Compared**

The three options are compared in terms of their execution performance, measured in executions per second (EPS).

**Pros and Cons of Each Approach**

1. **Push**:
	* Pros: Simple, widely supported, and efficient.
	* Cons: May not be as performant for large arrays due to the overhead of the `push()` method.
2. **Spread**:
	* Pros: More performant than `push()` for large arrays, as it avoids the overhead of modifying an array in place.
	* Cons: Less intuitive and may require more code to achieve the same result.
3. **Copy and push**:
	* Pros: Can be more efficient than `push()` for very large arrays, as it creates a new copy and modifies the copied array.
	* Cons: More complex and may incur additional overhead due to the creation of a temporary copy.

**Library and Purpose**

In this benchmark, none of the test cases explicitly use any libraries. However, the `slice()` method is used in one of the test cases, which is a built-in JavaScript method that returns a shallow copy of an array.

**Special JS Feature or Syntax**

There are no special JavaScript features or syntaxes mentioned in the provided code snippets. The only notable aspect is the use of the spread operator (`...`) in the `Spread` test case.

**Other Alternatives**

For appending items to an array, other alternatives could include:

1. Using `unshift()` instead of `push()`, which adds an item to the beginning of the array.
2. Using `concat()` instead of the spread operator, which creates a new array and returns it.
3. Using a library like Lodash or Ramda for more complex array operations.

Keep in mind that these alternatives may have different performance characteristics and use cases compared to the three options being benchmarked.

Related benchmarks:

Push vs spread vs copy and push, for appending single item (version: 1)

Comparing performance of: Push vs Spread vs Copy and push

Created: 5 years ago by: Registered User

Jump to the latest result

Push

Spread

Copy and push

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

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