ESLint

Next we install and configure ESLint. Let’s go into the root folder of our WordPress project and install eslint and eslint-config-prettier. Eslint-config-prettier is the one that is going to disable all the conflicting formatting from ESLint to give Prettier room to do it’s thing. You can install both with this command:

npm install --save-dev eslint eslint-config-prettier

Then add a file to the same root folder called .eslintrc.js with these contents:

"use strict";

module.exports = {
	env: {
		es6: true
	},
	extends: ["prettier"]
};

This enables ES6 syntax, ES6 global variables and starts using modern JavaScript settings that works nicely with Prettier.