nativeoverutil.md

Prefer native JS methods over user-land utils like Lodash

One Paragraph Explainer

Sometimes, using native methods is better than requiring lodash or underscore because those libraries can lead to performance loss or take up more space than needed The performance using native methods result in an overall ~50% gain which includes the following methods: Array.concat, Array.fill, Array.filter, Array.map, (Array|String).indexOf, Object.find, ...

Example: benchmark comparison - Lodash vs V8 (Native)

The graph below shows the mean of the benchmarks for a variety of Lodash methods, this shows that Lodash methods take on average 146.23% more time to complete the same tasks as V8 methods.

Code Example – Benchmark test on _.concat/Array.concat

const _ = require('lodash');
const __ = require('underscore');
const Suite = require('benchmark').Suite;
const opts = require('./utils'); //cf. https://github.com/Berkmann18/NativeVsUtils/blob/master/utils.js

const concatSuite = new Suite('concat', opts);
const array = [0, 1, 2];

concatSuite.add('lodash', () => _.concat(array, 3, 4, 5))
  .add('underscore', () => __.concat(array, 3, 4, 5))
  .add('native', () => array.concat(3, 4, 5))
  .run({ 'async': true });

Which returns this:

You can find a bigger list of benchmarks here or alternatively run this which would show the same but with colours.

Blog Quote: "You don't (may not) need Lodash/Underscore"

From the repo on this matter which focuses on Lodash and Underscore.

Lodash and Underscore are great modern JavaScript utility libraries, and they are widely used by Front-end developers. However, when you are targeting modern browsers, you may find out that there are many methods which are already supported natively thanks to ECMAScript5 [ES5] and ECMAScript2015 [ES6]. If you want your project to require fewer dependencies, and you know your target browser clearly, then you may not need Lodash/Underscore.

Example: Linting for non-native methods usage

There's an ESLint plugin which detects where you're using libraries but don't need to by warning you with suggestions (cf. example below).
The way you set it up is by adding the eslint-plugin-you-dont-need-lodash-underscore plugin to your ESLint configuration file:

{
  "extends": [
    "plugin:you-dont-need-lodash-underscore/compatible"
  ]
}

Example: detecting non-v8 util usage using a linter

Consider the file below:

const _ = require('lodash');
// ESLint will flag the line above with a suggestion
console.log(_.map([0, 1, 2, 4, 8, 16], x => `d${x}`));

Here's what ESLint would output when using the YDNLU plugin.

Of course, the example above doesn't seem realistic considering what actual codebases would have but you get the idea.