Benchmark: merge object by key from array with lodash

HTML Preparation code:

<script src="https://cdn.jsdelivr.net/npm/lodash@4.17.5/lodash.min.js"></script>

Script Preparation code:

var object = {
  'a': {
    'key': 'a',
    'foo': 123123,
    'bar': 123,
    'fobar': 456
  }
};

var array = [
  {
    'key': 'b',
    'foo': 67563,
    'bar': 6345,
    'fobar': 3425
  },
  {
    'key': 'c',
    'foo': 34532,
    'bar': 123412,
    'fobar': 534532
  },
  {
    'key': 'd',
    'foo': 1234321,
    'bar': 435234,
    'fobar': 346457
  },
  {
    'key': 'e',
    'foo': 23523,
    'bar': 124325,
    'fobar': 2134235
  },
  {
    'key': 'f',
    'foo': 1235213,
    'bar': 346346,
    'fobar': 213423
  }
];

Tests:

Array.prototype.reduce()
array.reduce(function(acc, cur) { acc[cur.key] = cur; return acc; }, Object.assign({}, object));
_.reduce()
_.reduce(array, function(acc, cur) { acc[cur.key] = cur; return acc; }, Object.assign({}, object));
_.reduce() with _.get()
_.reduce(array, function(acc, cur) { acc[_.get(cur, 'key')] = cur; return acc; }, Object.assign({}, object));
_.keyBy()
Object.assign({}, object, _.keyBy(array, 'key'));

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array.prototype.reduce()
_.reduce()
_.reduce() with _.get()
_.keyBy()

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2025 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/64.0.3282.140 Safari/537.36

Browser/OS: Chrome 64 on Mac OS X 10.13.3

View result in a separate tab

Test name	Executions per second
Array.prototype.reduce()	1020379.5 Ops/sec
_.reduce()	823283.4 Ops/sec
_.reduce() with _.get()	368213.0 Ops/sec
_.keyBy()	435519.1 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down what's being tested on MeasureThat.net.

**Benchmark Goal**
The goal of this benchmark is to compare the performance of three different approaches for merging an object from an array using JavaScript.

**Options Compared**

1. **Array.prototype.reduce()**: This approach uses the built-in `reduce()` method of the Array prototype to iterate over the array and merge the objects.
2. **_.reduce() (Lodash)**: This approach uses the same `reduce()` function, but wraps it in the Lodash library, which provides additional utility functions for common tasks like array manipulation.
3. **_.keyBy() (Lodash)**: This approach uses the `_keyBy()` function from Lodash to create an object with the array's keys as properties.

**Pros and Cons of Each Approach**

1. **Array.prototype.reduce()**:
	* Pros: Built-in method, easy to understand, no additional dependencies.
	* Cons: May not be optimized for performance, can be slower due to the overhead of a custom function.
2. **_.reduce() (Lodash)**:
	* Pros: Leverages the performance optimization already done by Lodash, provides additional utility functions that might be useful in other contexts.
	* Cons: Requires an additional dependency (Lodash), may add overhead due to the import and initialization process.
3. **_.keyBy() (Lodash)**:
	* Pros: More elegant and concise solution, leverages the optimized implementation of Lodash.
	* Cons: Requires an additional dependency (Lodash), may be slower due to the extra function call.

**Library: Lodash**
Lodash is a popular JavaScript library that provides a collection of utility functions for common tasks like array manipulation, object modification, and more. The `reduce()` and `_keyBy()` functions are part of this library.

**Special JS Feature/Syntax (None)**
There's no special JavaScript feature or syntax being used in these benchmarks.

Now, let's consider some alternative approaches that could be tested:

1. **Manual iteration**: Using a simple `for` loop to iterate over the array and merge the objects.
2. **Object.assign() with spread operator**: Using `Object.assign()` and the spread operator (`{ ... }`) to merge the objects.
3. **Library alternatives**: Testing other libraries like jQuery, Moment.js, or any other JavaScript utility library.

These alternative approaches could provide interesting insights into performance and trade-offs between different implementation strategies.

Related benchmarks:

merge object by key from array with lodash (version: 0)

Comparing performance of: Array.prototype.reduce() vs _.reduce() vs _.reduce() with _.get() vs _.keyBy()

Created: 6 years ago by: Guest

Jump to the latest result

Array.prototype.reduce()

_.reduce()

_.reduce() with _.get()

_.keyBy()

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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