.eslintrc.json

{
    "env": {
        "browser": true,
        "es6": true,
        "jest": true
    },
    "extends": [
        "eslint:recommended",
        "plugin:prettier/recommended",
        "prettier"
    ],
    "plugins": [
        "prettier"
    ],
    "parserOptions": {
        "ecmaVersion": 6,
        "sourceType": "module"
    },
    "rules": {
        "curly": [
            "error",
            "all"
        ],
        "eqeqeq": [
            "error",
            "always",
            { "null": "ignore" }
        ],
        "indent": [
            "error",
            2,
            { "SwitchCase": 1 }
        ],
        "max-len": [
            "error",
            {
                "code": 120,
                "ignoreUrls": true,
                "ignorePattern": ".+'[^\\s]+'(;|,)$"
            }
        ],
        "no-alert": "error",
        "no-console": "off",
        "no-case-declarations": "error",
        "no-undef": "off",
        "no-unused-vars": "warn",
        "prettier/prettier": [
            "off",
            {"usePrettierrc": true}
        ],
        "quotes": [
            "error",
            "single",
            { "avoidEscape": true, "allowTemplateLiterals": false }
        ],
        "semi": ["error", "never"]
    }
}