.eslintrc.js

module.exports = {
    "env": {
        "browser": true,
        "commonjs": true,
        "node": true
    },
    "parserOptions": {
        "sourceType": "module",
        "ecmaVersion": 2018
    },
    "extends": "eslint:recommended",
    "globals": {
        "Promise": true,
        "Map": true,
        'expect': true,
        'it': true,
        'describe': true,
        'beforeEach': true,
        'writer': true,
        'substance': true
    },
    "rules": {
        // 0 - off, 1 - warning, 2 - error
        "indent": [2, 4, {"SwitchCase": 1}],
        "semi": [0, "never"],
        "comma-dangle": [2, "only-multiline"],
        "no-cond-assign": 2,
        "no-console": [2, {allow: ["warn", "log", "info", "error", "assert"]}],
        "no-constant-condition": 2,
        "no-control-regex": 2,
        "no-debugger": 1,
        "no-dupe-args": 2,
        "no-dupe-keys": 2,
        "no-duplicate-case": 2,
        "no-empty": 0,
        "no-empty-character-class": 2,
        "no-ex-assign": 2,
        "no-extra-boolean-cast": 2,
        "no-extra-parens": 0,
        "no-extra-semi": 2,
        "no-func-assign": 2,
        "no-inner-declarations": 2,
        "no-invalid-regexp": 2,
        "no-irregular-whitespace": 2,
        "no-negated-in-lhs": 2,
        "no-obj-calls": 2,
        // turned of as we want to be able to use this.hasOwnProperty() for instance
        "no-prototype-builtins": 0,
        "no-regex-spaces": 2,
        "no-sparse-arrays": 0,
        "no-unexpected-multiline": 2,
        "no-unreachable": 2,
        // "no-unsafe-finally": 2,
        "use-isnan": 2,
        "valid-jsdoc": 0,
        "valid-typeof": 2,
        "strict": 0, // [2, "safe"],

        // Best practices
        "accessor-pairs": 0,
        "array-callback-return": 2,
        "block-scoped-var": 2,
        "complexity": [0, 10],
        "consistent-return": 0,
        "curly": [2, "multi-line"],
        "default-case": 2,
        "dot-location": [2, 'property'],
        "dot-notation": 0,
        "eqeqeq": 2,
        "guard-for-in": 2,
        "no-alert": 2,
        "no-caller": 2,
        "no-case-declarations": 2,
        "no-div-regex": 2,
        "no-else-return": 0,
        "no-empty-function": 0,
        // if you want to check for undefined or null use lodash/isNil
        "no-eq-null": 2,
        "no-eval": 2,
        "no-extend-native": 2,
        "no-extra-bind": 2,
        "no-extra-label": 2,
        "no-fallthrough": 2,
        "no-floating-decimal": 2,
        "no-implicit-coercion": 2,
        "no-implicit-globals": 2,
        "no-implied-eval": 2,
        "no-invalid-this": 2,
        "no-iterator": 2,
        "no-labels": 2,
        "no-lone-blocks": 0,
        "no-loop-func": 2,
        "no-magic-numbers": 0,
        "no-multi-spaces": 2,
        "no-multi-str": 0,
        "no-native-reassign": 2,
        "no-new": 0,
        "no-new-func": 0,
        "no-new-wrappers": 2,
        "no-octal": 2,
        "no-octal-escape": 2,
        "no-param-reassign": 0,
        "no-proto": 2,
        "no-redeclare": 2,
        "no-return-assign": 2,
        "no-script-url": 2,
        "no-self-assign": 2,
        "no-self-compare": 2,
        "no-sequences": 2,
        "no-throw-literal": 2,
        "no-unmodified-loop-condition": 2,
        "no-unused-expressions": 2,
        "no-unused-labels": 2,
        "no-useless-call": 2,
        "no-useless-concat": 2,
        //"no-useless-escape": 2,
        "no-void": 2,
        "no-warning-comments": 0,
        "no-with": 2,
        "radix": 2,
        "vars-on-top": 0,
        "wrap-iife": 2,
        "yoda": 0,
        // variables
        "init-declarations": 0,
        "no-catch-shadow": 2,
        "no-delete-var": 2,
        "no-label-var": 2,
        "no-restricted-globals": 2,
        "no-shadow": 0,
        "no-shadow-restricted-names": 2,
        "no-undef": 2,
        "no-undef-init": 2,
        "no-undefined": 0,
        "no-unused-vars": 1,
        "no-use-before-define": [2, {"functions": false}]
    }
};