.eslintrc.json

{
  "root": true,
  "extends": "eslint:recommended",

  "env": {
    "browser": false,
    "es6": true,
    "mocha": true,
    "node": true
  },

  "parserOptions":{
    "ecmaVersion": 9,
    "sourceType": "module",
    "ecmaFeatures": {
      "modules": true,
      "experimentalObjectRestSpread": true
    }
  },

  "globals": {
    "document": false,
    "navigator": false,
    "window": false
  },

  "rules": {
    "accessor-pairs": 2,
    "array-bracket-newline": [1, "consistent"],
    "array-bracket-spacing": [1, "never"],
    "array-callback-return": 1,
    "array-element-newline": [1, "consistent"],
    "arrow-body-style": 0,
    "arrow-parens": [1, "as-needed"],
    "arrow-spacing": [1, { "before": true, "after": true }],
    "block-scoped-var": 1,
    "block-spacing": [1, "always"],
    "brace-style": [1, "1tbs", { "allowSingleLine": true }],
    "callback-return": 0,
    "camelcase": [0, { "allow": [] }],
    "capitalized-comments": 0,
    "class-methods-use-this": 0,
    "comma-dangle": [1, "never"],
    "comma-spacing": [1, { "before": false, "after": true }],
    "comma-style": [1, "last"],
    "computed-property-spacing": 1,
    "consistent-return": 0,
    "consistent-this": 1,
    "constructor-super": 2,
    "curly": [1, "multi-line", "consistent"],
    "default-case": 1,
    "dot-location": [1, "property"],
    "dot-notation": 1,
    "eol-last": 1,
    "eqeqeq": [1, "allow-null"],
    "for-direction": 1,
    "func-call-spacing": 2,
    "generator-star-spacing": [1, { "before": true, "after": true }],
    "handle-callback-err": [2, "^(err|error)$"],
    "indent": [1, 2, { "SwitchCase": 1 }],
    "key-spacing": [1, { "beforeColon": false, "afterColon": true }],
    "keyword-spacing": [1, { "before": true, "after": true }],
    "linebreak-style": [1, "unix"],
    "new-cap": [1, { "newIsCap": true, "capIsNew": false }],
    "new-parens": 2,
    "no-alert": 1,
    "no-array-constructor": 1,
    "no-async-promise-executor": 1,
    "no-caller": 2,
    "no-case-declarations": 1,
    "no-class-assign": 2,
    "no-cond-assign": 2,
    "no-const-assign": 2,
    "no-constant-condition": [1, { "checkLoops": false }],
    "no-control-regex": 2,
    "no-debugger": 2,
    "no-delete-var": 2,
    "no-dupe-args": 2,
    "no-dupe-class-members": 2,
    "no-dupe-keys": 2,
    "no-duplicate-case": 2,
    "no-duplicate-imports": 0,
    "no-else-return": 0,
    "no-empty-character-class": 2,
    "no-empty-function": 0,
    "no-empty-pattern": 0,
    "no-empty": [1, { "allowEmptyCatch": true }],
    "no-eval": 0,
    "no-ex-assign": 2,
    "no-extend-native": 2,
    "no-extra-bind": 1,
    "no-extra-boolean-cast": 1,
    "no-extra-label": 1,
    "no-extra-parens": [1, "all",
      {
        "conditionalAssign": false,
        "returnAssign": false,
        "nestedBinaryExpressions": false,
        "ignoreJSX": "multi-line",
        "enforceForArrowConditionals": false
      }
    ],
    "no-extra-semi": 1,
    "no-fallthrough": 2,
    "no-floating-decimal": 2,
    "no-func-assign": 2,
    "no-global-assign": 2,
    "no-implicit-coercion": 2,
    "no-implicit-globals": 1,
    "no-implied-eval": 2,
    "no-inner-declarations": [1, "functions"],
    "no-invalid-regexp": 2,
    "no-invalid-this": 1,
    "no-irregular-whitespace": 2,
    "no-iterator": 2,
    "no-label-var": 2,
    "no-labels": 2,
    "no-lone-blocks": 2,
    "no-lonely-if": 2,
    "no-loop-func": 1,
    "no-mixed-requires": 1,
    "no-mixed-spaces-and-tabs": 2,
    "no-multi-assign": 0,
    "no-multi-spaces": 1,
    "no-multi-str": 2,
    "no-multiple-empty-lines": [1, { "max": 1 }],
    "no-native-reassign": 2,
    "no-negated-condition": 0,
    "no-negated-in-lhs": 2,
    "no-new-func": 2,
    "no-new-object": 2,
    "no-new-require": 2,
    "no-new-symbol": 1,
    "no-new-wrappers": 2,
    "no-new": 1,
    "no-obj-calls": 2,
    "no-octal-escape": 2,
    "no-octal": 2,
    "no-path-concat": 1,
    "no-proto": 2,
    "no-prototype-builtins": 0,
    "no-redeclare": 2,
    "no-regex-spaces": 2,
    "no-restricted-globals": 2,
    "no-return-assign": 1,
    "no-return-await": 2,
    "no-script-url": 1,
    "no-self-assign": 1,
    "no-self-compare": 1,
    "no-sequences": 2,
    "no-shadow-restricted-names": 2,
    "no-shadow": 0,
    "no-spaced-func": 2,
    "no-sparse-arrays": 2,
    "no-template-curly-in-string": 0,
    "no-this-before-super": 2,
    "no-throw-literal": 2,
    "no-trailing-spaces": 1,
    "no-undef-init": 2,
    "no-undef": 2,
    "no-unexpected-multiline": 2,
    "no-unneeded-ternary": [1, { "defaultAssignment": false }],
    "no-unreachable-loop": 1,
    "no-unreachable": 2,
    "no-unsafe-assignment": 0,
    "no-unsafe-call": 0,
    "no-unsafe-finally": 2,
    "no-unsafe-member-access": 0,
    "no-unsafe-negation": 2,
    "no-unsafe-optional-chaining": 0,
    "no-unsafe-return": 0,
    "no-unused-expressions": 2,
    "no-unused-vars": [1, { "vars": "all", "args": "after-used" }],
    "no-use-before-define": 0,
    "no-useless-call": 2,
    "no-useless-catch": 0,
    "no-useless-escape": 0,
    "no-useless-rename": 1,
    "no-useless-return": 1,
    "no-var": 1,
    "no-void": 1,
    "no-warning-comments": 0,
    "no-with": 2,
    "object-curly-spacing": [1, "always", { "objectsInObjects": true }],
    "object-shorthand": 1,
    "one-var": [1, { "initialized": "never" }],
    "operator-linebreak": [0, "after", { "overrides": { "?": "before", ":": "before" } }],
    "padded-blocks": [1, { "switches": "never" }],
    "prefer-const": [1, { "destructuring": "all", "ignoreReadBeforeAssign": false }],
    "prefer-promise-reject-errors": 1,
    "quotes": [1, "single", "avoid-escape"],
    "radix": 2,
    "rest-spread-spacing": 1,
    "semi-spacing": [1, { "before": false, "after": true }],
    "semi-style": 1,
    "semi": [1, "always"],
    "space-before-blocks": [1, "always"],
    "space-before-function-paren": [1, { "anonymous": "never", "named": "never", "asyncArrow": "always" }],
    "space-in-parens": [1, "never"],
    "space-infix-ops": 1,
    "space-unary-ops": [1, { "words": true, "nonwords": false }],
    "spaced-comment": [0, "always", { "markers": ["global", "globals", "eslint", "eslint-disable", "*package", "!", ","] }],
    "strict": 2,
    "switch-colon-spacing": 1,
    "symbol-description": 1,
    "template-curly-spacing": [2, "never"],
    "template-tag-spacing": [2, "never"],
    "unicode-bom": 1,
    "use-isnan": 2,
    "valid-jsdoc": 1,
    "valid-typeof": 2,
    "wrap-iife": [1, "any"],
    "yoda": [1, "never"]
  }
}