.eslintrc.json

{
    "env": {
        "browser": true,
        "es6": true,
        "mocha": true,
        "node": true
    },
    "extends": [
        "eslint:recommended"
    ],
    "parser": "@babel/eslint-parser",
    "parserOptions": {
        "ecmaFeatures": {
            "jsx": true
        },
        "ecmaVersion": 2018,
        "sourceType": "module",
        "allowImportExportEverywhere": true
    },
    "plugins": [
        "mocha"
    ],
    "rules": {
        "accessor-pairs": [
            "error",
            {
                "getWithoutSet": true
            }
        ],
        "curly": "warn",
        "eqeqeq": "error",
        "func-call-spacing": [
            "error",
            "never"
        ],
        "indent": [
            "error",
            4
        ],
        "keyword-spacing": [
            "warn",
            {
                "before": true,
                "after": true
            }
        ],
        "linebreak-style": [
            "error",
            "unix"
        ],
        "max-len": [
            "warn", {
                "code": 120,
                "ignoreComments": true
            }
        ],
        "no-console": "warn",
        "no-eval": "error",
        "no-loop-func": "error",
        "no-trailing-spaces": "warn",
        "no-underscore-dangle": "warn",
        "no-unused-vars": "warn",
        "no-use-before-define": "error",
        "no-var": "error",
        "prefer-const": "error",
        "quotes": [
            "error",
            "single"
        ],
        "semi": [
            "error",
            "always"
        ],
        "mocha/no-exclusive-tests": "error"
    }
}