Benchmark: Lodash uniqBy vs Reduce uniqBy

HTML Preparation code:

<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Script Preparation code:

var testFiles = _.range(_.random(100)).map(x => ({
    
        id: _.random(1, 10),
    
}));

Tests:

Lodash
_.uniqBy(testFiles,"id")
Reduce
testFiles.reduce((accumulator, item) => { if (item === null) { return accumulator; } const keyExist = accumulator.some((i) => i["id"] === item["id"]); return keyExist === true ? accumulator : [...accumulator, item]; }, []);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Lodash
Reduce

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 17_2_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) FxiOS/121.1 Mobile/15E148 Safari/605.1.15

Browser/OS: Mobile Safari 17 on iOS 17.2.1

View result in a separate tab

Test name	Executions per second
Lodash	1051151.5 Ops/sec
Reduce	507165.0 Ops/sec

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

LLMs can make mistakes. Check important info.

**Overview of the Benchmark**

The provided JSON represents a JavaScript microbenchmark created on MeasureThat.net. The benchmark compares the performance of two approaches for filtering an array of objects by a key: Lodash's `uniqBy` function and the built-in `reduce` method.

**Options Compared**

Two options are compared:

1. **Lodash's `uniqBy`**: This is a utility function from the Lodash library that takes an array of objects and a key as input, and returns a new array with duplicate entries removed based on the specified key.
2. **Built-in `reduce` method**: This is a built-in JavaScript method that applies a reduction function to each element in an array, reducing it to a single output value.

**Pros and Cons**

### Lodash's `uniqBy`

Pros:

* Convenient and concise syntax
* Handles edge cases, such as empty arrays or arrays with no duplicates
* Well-tested and widely adopted

Cons:

* Adds overhead due to the library's inclusion in the benchmark code
* May not be optimal for very large datasets

### Built-in `reduce` method

Pros:

* Native performance, eliminating the need for a library
* Flexibility in customization through the reduction function
* Can handle large datasets efficiently

Cons:

* Requires manual implementation of the reduction logic
* May require additional setup or testing for edge cases

**Library: Lodash**

Lodash is a popular JavaScript utility library that provides a wide range of functions for common tasks, such as array manipulation, object transformation, and more. In this benchmark, `uniqBy` is used to filter an array of objects by a key.

**Test Case Analysis**

The test cases compare the performance of each approach:

1. **Lodash's `uniqBy`**: The `uniqBy` function is called with the `testFiles` array and the `"id"` key as arguments.
2. **Built-in `reduce` method**: The `reduce` method is implemented using a custom reduction function that checks for duplicate keys in the accumulator.

**Device-Specific Feature: iOS 17**

The benchmark result shows a difference in performance between the two approaches on an iOS 17 device, with Lodash's `uniqBy` outperforming the built-in `reduce` method. This suggests that there may be some underlying differences in how the JavaScript engine optimizes or executes these two functions on this specific platform.

**Alternative Approaches**

Other alternatives to compare in this benchmark could include:

* Using a different filtering library, such as Moment.js or Fast.js
* Implementing the filtering logic using other JavaScript methods, like `filter` or `every`
* Comparing the performance of Lodash's `uniqBy` with the built-in `reduce` method on different devices (e.g., desktop vs. mobile)

Related benchmarks:

Lodash uniqBy vs Reduce uniqBy (version: 0)

Filtering array of objects by key

Comparing performance of: Lodash vs Reduce

Created: 4 years ago by: Guest

Jump to the latest result

Lodash

Reduce

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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