Benchmark: Difference between lists vs filtering on property

HTML Preparation code:

<script src="https://cdn.jsdelivr.net/npm/lodash@4.17.4/lodash.min.js"></script>

Script Preparation code:

var allItems = Array(1000).fill().map((_, i) => ({ id: i, selected: i % 2 == 0 }));
var selectedItems = allItems.filter((_, i) => i % 2 == 0);

Tests:

2 lists, difference between lists
const newListDiff = _.differenceWith(allItems, selectedItems, _.isEqual); console.log({newListDiff})
1 list, filtering on selected property
const newListFilter = allItems.filter(item => !item.selected); console.log({newListFilter});

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
2 lists, difference between lists
1 list, filtering on selected property

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):

LLMs can make mistakes. Check important info.

Let's break down the benchmark and its test cases.

**Benchmark Overview**

The benchmark measures the performance of two approaches to achieve a similar result:

1. Using `_.differenceWith` from Lodash to find the difference between two lists (`allItems` and `selectedItems`).
2. Filtering an array directly using the `filter` method with a callback function that checks if an item's `selected` property is false.

**Options Compared**

The benchmark compares two options:

1. Using `_.differenceWith` from Lodash, which returns a new array containing elements that are present in `allItems`, but not in `selectedItems`, and vice versa.
2. Filtering an array directly using the `filter` method with a callback function that checks if an item's `selected` property is false.

**Pros and Cons of Each Approach**

1. **_.differenceWith (Lodash)**:
	* Pros:
		+ More explicit and readable code
		+ Can handle more complex comparison logic (e.g., using different comparison functions)
		+ Returns a new array, avoiding modifying the original arrays.
	* Cons:
		+ May be slower due to the overhead of creating and using Lodash functions.
		+ Requires an additional library dependency (Lodash).
2. **Filtering with `filter`**:
	* Pros:
		+ Faster execution, as it uses a built-in array method
		+ No additional library dependencies required
	* Cons:
		+ Code may be less readable and more verbose due to the need for callback functions.
		+ May modify the original arrays (depending on the implementation).

**Library: Lodash**

The benchmark uses Lodash version 4.17.4, which provides the `_.differenceWith` function. Lodash is a popular utility library for JavaScript that provides a collection of functional programming helpers.

**Special JS Feature/Syntax: None**

There are no special JavaScript features or syntax used in this benchmark beyond standard ES6+ language features and Lodash's `_.differenceWith` function.

**Other Alternatives**

If you're interested in alternative approaches, consider the following:

1. Using `Array.prototype.filter()` with a callback function that checks if an item's `selected` property is false.
2. Using a library like `pmap` or `fast-est` to compare arrays and measure performance.
3. Implementing your own custom implementation using JavaScript loops and conditional statements.

Keep in mind that the best approach may depend on specific requirements, such as performance, code readability, or library dependencies.

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/113.0.0.0 Safari/537.36

Browser/OS: Chrome 113 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
2 lists, difference between lists	7.1 Ops/sec
1 list, filtering on selected property	53422.8 Ops/sec

Related benchmarks:

Difference between lists vs filtering on property (version: 0)

Comparing performance of: 2 lists, difference between lists vs 1 list, filtering on selected property

Created: one year ago by: Registered User

Jump to the latest result

2 lists, difference between lists

1 list, filtering on selected property

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):