eslint-config

Preferring ES6, readability and low ambiguities. Extends the recommended ruleset with some useful additions.

Setup Guide

Follow the below steps to setup ESLint using this custom configuration

JavaScript

• npm install eslint --save-dev
• npm install @thomaschaplin/eslint-config --save-dev
• touch .eslintrc
• Add the below snippet into your .eslintrc file
• Add the below script snippet into your package.json file

.eslintrc snippet

{
    "extends": ["@thomaschaplin"]
}

package.json snippet

"scripts": {
    "lint:js": "./node_modules/eslint/bin/eslint.js 'src/**/*.js'",
    "lintFull": "npm run lint:js -- --fix"
}

TypeScript

Follow all of the steps for the JavaScript setup

• npm install typescript --save-dev
• npm install @typescript-eslint/eslint-plugin --save-dev
• npm install @typescript-eslint/parser --save-dev
• Add the below snippet into your .eslintrc file
• Add the below script snippet into your package.json file

.eslintrc snippet

{
    "extends": ["@thomaschaplin"],
    "plugins": ["@typescript-eslint"],
    "parser": "@typescript-eslint/parser",
    "parserOptions": {
        "ecmaVersion": 6,
        "sourceType": "module",
        "ecmaFeatures": {
            "modules": true
        }
    }
}

package.json snippet

"scripts": {
    "lint:ts": "./node_modules/eslint/bin/eslint.js 'src/**/*.ts'",
    "lintFull": "npm run lint:ts -- --fix"
}

Rules in detail

Environments: node, es6, browser

Unless noted, all rules are errors.

Rule	Description
arrow-parens	Always wrap function arguments in brackets.
brace-style	Curly brackets start after the keyword, not underneath.
comma-dangle	Dangling commas in multiline objects, functions, arrays.
complexity	Maximum cyclomatic complexity of 3 to enforce highly maintaineable code (warning).
curly	Curly brackets after if statements to avoid ambiguity when line breaks occur.
eol-last	Empty line at the end of the file.
func-call-spacing	Brackets () to invoke a function have to stand right next to the function name.
global-require	require() statements should be at the top of the file (warning).
linebreak-style	UNIX linebreaks.
no-await-in-loop	Disallow await in loops (should use Promise.all() instead).
no-default-export	Only allow named exports for increased consistency and clarity when importing modules.
no-floating-decimal	Numbers have to be clear, i.e. 0.4 instead of .4.
no-implicit-coercion	Converting types from one to another have to be explicit.
no-lone-blocks	No curly brackets unless necessary.
no-lonely-if	Use else if instead of a lonely if wrapped inside an else.
no-loop-func	Functions cannot be declared inside loops, they should be declared outside.
no-template-curly-in-string	Avoid confusion whether a string is templated or not.
no-throw-literal	Throw errors explicitly, not just strings or values.
no-var	Use ES6 block-scopedconst and let, never var.
one-var	Don't declare multiple variables in one line.
prefer-const	let should only be used where reassignment is necessary.
prefer-promise-reject-errors	Promises should be rejected with a clear error, not a simple value.
prefer-spread	Use ES6 spread operator instead of difficult to understand ES5 .apply().
prefer-template	Use template strings instead of string concatenation (warning).
quotes	Use unescaped double quotes.
require-await	async functions should perform an await, otherwise async keyword is unnecessary.
semi	Don't use semicolons.
yoda	Don't use unintuitive conditions.