.eslintrc.json

{
    "env": {
        "es6": true,
        "node": true,
        "mocha": true
    },
    "parserOptions": {
        "ecmaVersion": 9
    },
    "extends": "eslint:recommended",
    "rules": {
        "comma-spacing":               ["error"],
        "eqeqeq":                      ["error", "always"],
        "indent":                      ["error", 4],
        "key-spacing":                 ["error"],
        "keyword-spacing":             ["error"],
        "linebreak-style":             ["error", "unix"],
        "no-multi-spaces":             ["error"],
        "no-unused-vars":              ["error", {"args": "none"}],
        "no-var":                      ["error"],
        "no-console":                  ["off"],
        "prefer-const":                ["error"],
        "prefer-arrow-callback":       ["error"],
        "quotes":                      ["error", "single"],
        "semi":                        ["error"],
        "strict":                      ["error", "global"],
        "space-before-blocks":         ["error"],
        "space-before-function-paren": ["error", {"anonymous": "always", "named": "never"}]
    }
}