Benchmark: Lodash "uniqWith" "unionBy" "uniqBy" 8

HTML Preparation code:

<script src='https://cdn.jsdelivr.net/npm/lodash@4.17.10/lodash.min.js'></script>

Script Preparation code:

var users = [
  { 'name': 'barney',  'age': 36 },
  { 'name': 'pebbles', 'age': 5 }
];

var newUsers = [
  { 'name': 'fred',    'age': 40 },
  { 'name': 'barney',  'age': 36 },
  { 'name': 'pebbles', 'age': 2 }
];

for(let i = 0; i < 2000; i++) {
  var newUser = { 'name': 'user_' + i, 'age': Math.floor(Math.random() * i) };
  newUsers.push(newUser);
}

Tests:

uniqWith
const unionUsers1 = _.uniqWith(newUsers.concat(users), _.isEqual);
uniqBy
const unionUsers1 = _.uniqBy(newUsers.concat(users), (val) => val.toString());

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
uniqWith
uniqBy

Fastest: N/A

Slowest: N/A

Latest run results:

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

LLMs can make mistakes. Check important info.

**Overview of the Benchmark**

The provided benchmark is designed to test the performance of two functions in Lodash: `uniqWith` and `uniqBy`. The test aims to determine which function is more efficient for unionizing arrays with varying levels of complexity.

**What is being tested?**

In this benchmark, the following functions are being compared:

1. `_.uniqWith(users.concat(newUsers), _.isEqual)`: This function uses `_.isEqual` as a comparison function to check for equality between objects in the input arrays.
2. `_.uniqBy(newUsers.concat(users), (val) => val.toString())`: This function uses a custom comparison function that converts each object value to a string using `toString()`.

**Pros and Cons of each approach**

1. **`.uniqWith(_.isEqual)`**
	* Pros:
		+ Simple and straightforward implementation
		+ Fast performance since it only checks for reference equality between objects
	* Cons:
		+ May not work well with non-object values or complex data structures
		+ May be slower than `.uniqBy` due to the overhead of creating a comparison function
2. **`.uniqBy((val) => val.toString())`**
	* Pros:
		+ Can handle any type of value, including non-objects and complex data structures
		+ Often faster performance since it avoids the need for expensive equality checks
	* Cons:
		+ Requires converting each object value to a string, which can lead to slower performance if not done efficiently
		+ May not work well with large datasets or high-performance requirements

**Lodash libraries and functions**

In this benchmark, Lodash is used as the external library. The `_.uniqWith` and `_.uniqBy` functions are part of the Lodash utility library.

**Other considerations**

* The test uses a synthetic dataset generated by JavaScript code to create two large arrays of user objects.
* The `concat()` method is used to combine the input arrays, which can lead to slower performance compared to using `push()` or other methods that avoid creating intermediate arrays.
* The benchmark is run on a Desktop platform with Chrome 116 browser, which may not be representative of all possible environments.

**Alternatives**

Some alternative approaches for unionizing arrays include:

1. Using the `Set` data structure: Create a Set from each input array and then merge them using `Set.union()`.
2. Using `Array.prototype.reduce()` or `Array.prototype.forEach()`: Iterate over one of the input arrays and add elements to the other array.
3. Using a custom implementation with loops: Write a loop-based implementation that iterates over both input arrays and adds unique elements to a result array.

These alternatives may offer different trade-offs in terms of performance, readability, and maintainability compared to using `_.uniqWith` or `_.uniqBy`.

Related benchmarks:

Lodash "uniqWith" "unionBy" "uniqBy" 8 (version: 0)

Comparing performance of: uniqWith vs uniqBy

Created: 2 years ago by: Guest

Jump to the latest result

uniqWith

uniqBy

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):