Benchmark: pickby vs filter on object keys only

HTML Preparation code:

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

Script Preparation code:

var obj = {}
for (let i = 0; i < 1000; i++) {
  obj[String(i)] = Math.floor(Math.random() * 6) + 1
} 
var predicate = v => v % 2 === 0;

Tests:

pickby
Object.keys(_.pickBy(obj, predicate))
filter
Object.keys(obj).filter((e) => predicate(obj[e]))

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
pickby
filter

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks on MeasureThat.net.

The provided benchmark is designed to compare two approaches: `pickby` and `filter`. The goal is to measure which approach is faster when filtering an object based on its keys only. Let's break it down:

**Script Preparation Code**

The script preparation code creates a large object `obj` with 1000 properties, each assigned a random value between 1 and 6 (inclusive). This object will be used as the input for our benchmark.

**Html Preparation Code**

The HTML preparation code includes a reference to Lodash.js, a popular JavaScript library that provides functional programming utilities. Specifically, it loads the `lodash.min` module, which contains the `pickby` function we'll be using in the benchmark.

**Benchmark Definition**

The benchmark definition is split into two individual test cases:

1. **Pickby**: `Object.keys(_.pickBy(obj, predicate))`
This line of code uses the `pickby` function from Lodash to create a new object that only includes properties from `obj` where the value satisfies the condition defined in the `predicate` function. The resulting object's keys are then returned as an array using `Object.keys()`.
2. **Filter**: `Object.keys(obj).filter((e) => predicate(obj[e]))`
This line of code uses the `filter` method to create a new array that includes only elements from `obj` where the value satisfies the condition defined in the `predicate` function.

**Options Compared**

The benchmark is comparing two options:

1. **Pickby**: Uses Lodash's `pickby` function to filter and map the object.
2. **Filter**: Uses JavaScript's built-in `filter` method on an array created by iterating over the object's keys.

**Pros and Cons**

Here are some pros and cons of each approach:

* **Pickby**:
	+ Pros: More concise and readable, leveraging Lodash's optimized implementation.
	+ Cons: May introduce additional overhead due to Lodash's function call and module loading.
* **Filter**:
	+ Pros: No additional overhead beyond JavaScript's built-in methods.
	+ Cons: Less concise and may require more lines of code.

**Library and Purpose**

In this benchmark, Lodash is used as a library to provide the `pickby` function. The purpose of `pickby` is to create a new object with only the desired properties, making it easier to filter and map objects in a functional programming style.

**Special JS Feature or Syntax**

None mentioned in this specific benchmark.

**Alternatives**

Some alternative approaches could be:

* Using a custom implementation of `pickby` without Lodash.
* Using other filtering libraries like Moment.js or jQuery.
* Implementing a manual loop to filter the object's keys and values.
* Using a different JavaScript engine or optimization technique, such as Parallelogram or WebAssembly.

Keep in mind that these alternatives may not provide the same level of performance or conciseness as the original benchmark.

Latest run results:

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

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/105.0.0.0 Safari/537.36

Browser/OS: Chrome 105 on Linux

View result in a separate tab

Test name	Executions per second
pickby	13979.3 Ops/sec
filter	7293.9 Ops/sec

Related benchmarks:

pickby vs filter on object keys only (version: 0)

Comparing performance of: pickby vs filter

Created: 2 years ago by: Guest

Jump to the latest result

pickby

filter

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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