.eslintrc

{
  "extends": [
    "eslint:recommended",
    "plugin:node/recommended"
  ],
  "parserOptions": {
    "ecmaVersion": 11,
    "sourceType": "script"
  },
  "env": {
    "node": true,
    "es6": true,
    "es2017": true,
    "es2020": true,
    "browser": true,
    "shared-node-browser": true
  },
  "overrides": [
    {
      "files": ["test/*js", "test/**/*.js", "*.test.js"],
      "rules": {
        "max-nested-callbacks": "off",
        "node/global-require": "off",
        "node/no-process-env": "off",
        "node/no-sync": "off",
        "class-methods-use-this": "off",
        "node/handle-callback-err": "off",
        "no-unused-expressions": "off",
        "no-unused-vars": "off"
      },
      "globals": {
        "sinon": true,
        "describe": true,
        "it": true,
        "expect": true,
        "proxyquire": true
      },
      "env": {
        "mocha": true
      }
    },
    {
      "files": ["config.js"],
      "rules": {
        "node/no-process-env": "off",
        "node/no-process-exit": "off",
        "no-process-exit": "off"
      }
    }
  ],

  "rules": {
    // "Possible Errors" Rules
    "no-console": "warn",
    "no-extra-parens": ["error", "all", {
      "ignoreJSX": "multi-line",
      "returnAssign": false,
      "nestedBinaryExpressions": false,
      "enforceForArrowConditionals": true
    }],
    "no-template-curly-in-string": "error",

    // "Best Practices" Rules
    "array-callback-return": "error",
    "class-methods-use-this": "error",
    "curly": "error",
    "dot-location": ["error", "property"],
    "dot-notation": "error",
    "eqeqeq": "error",
    "guard-for-in": "error",
    "no-alert": "warn",
    "no-else-return": "error",
    "no-eq-null": "error",

    "no-eval": "error",
    "no-extra-bind": "error",
    "no-extra-label": "error",
    "no-floating-decimal": "error",
    "no-implicit-coercion": "error",
    "no-implied-eval": "error",
    "no-lone-blocks": "error",
    "no-loop-func": "error",
    "no-magic-numbers": "off",
    "no-new": "error",
    "no-new-wrappers": "error",
    "no-return-await": "error",
    "no-self-compare": "error",
    "no-sequences": "error",
    "no-unmodified-loop-condition": "error",
    "no-unused-expressions": "error",
    "no-useless-call": "error",
    "no-useless-concat": "error",
    "no-useless-return": "error",
    "no-void": "error",
    "no-with": "error",
    "prefer-promise-reject-errors": "error",
    "radix": "error",
    "require-await": "error",
    "wrap-iife": "error",
    "yoda": "error",

    // "Variables" Rules
    "no-label-var": "error",
    "no-shadow-restricted-names": "error",
    "no-undef-init": "error",
    "no-undefined": "error",
    "no-use-before-define": "error",

    // "Node.js and CommonJS" Rules
    "node/global-require": "error",
    "node/handle-callback-err": "error",
    "node/no-mixed-requires": "error",
    "node/no-new-require": "error",
    "node/no-process-env": "error",
    "node/no-process-exit": "error",
    "node/no-sync": "error",

    // "Stylistic" Rules
    "brace-style": "error",
    "comma-dangle": ["error", "always-multiline"],
    "comma-spacing": "error",
    "comma-style": "error",
    "computed-property-spacing": "error",
    "consistent-this": "error",
    "eol-last": "error",
    "func-call-spacing": "error",
    "indent": [2, 2, {"SwitchCase": 1}],
    "jsx-quotes": ["error", "prefer-single"],
    "key-spacing": "error", // Maybe not
    "keyword-spacing": "error",
    "lines-between-class-members": ["error", "always", { "exceptAfterSingleLine": true }],
    "max-nested-callbacks": ["error", 5],
    "new-cap": "error",
    "new-parens": "error",
    "newline-per-chained-call": ["error", { "ignoreChainWithDepth": 3 }],
    "no-array-constructor": "error",
    "no-lonely-if": "error",
    "no-multiple-empty-lines": "error",
    "no-negated-condition": "error",
    "no-nested-ternary": "error",
    "no-trailing-spaces": "error",
    "no-unneeded-ternary": "error",
    "no-whitespace-before-property": "error",
    "object-curly-newline": ["error", { "multiline": true }],
    "object-curly-spacing": "error",
    "one-var-declaration-per-line": "error",
    "operator-assignment": "error",
    "operator-linebreak": ["error", "after"],
    "prefer-object-spread": "error",
    "quote-props": ["error", "as-needed"],
    "quotes": ["error", "single"],
    "semi": ["error", "always", { "omitLastInOneLineBlock": false }],
    "semi-spacing": "error",
    "semi-style": "error",
    "space-before-blocks": "error",
    "space-before-function-paren": ["error", "never"],
    "space-in-parens": "error",
    "space-infix-ops": "error",
    "space-unary-ops": "error",
    "spaced-comment": "error",
    "switch-colon-spacing": "error",
    "wrap-regex": "error",


    // "ECMAScript 6" Rules
    "arrow-parens": "error",
    "arrow-spacing": "error",
    "no-confusing-arrow": "error",
    "no-duplicate-imports": "error",
    "no-useless-computed-key": "error",
    "no-useless-constructor": "error",
    "no-useless-rename": "error",
    "no-var": "error",
    "object-shorthand": "error",
    "prefer-arrow-callback": "error",
    "prefer-const": "error",
    "prefer-numeric-literals": "error",
    "prefer-rest-params": "error",
    "prefer-spread": "error",
    "prefer-template": "error",
    "rest-spread-spacing": "error",
    "symbol-description": "error",
    "template-curly-spacing": "error",
    "yield-star-spacing": "error"
  }
}