ESLint config file for node.js + ES6 projects.

.eslintrc.json

{
  "env": {
    "node": true,
    "es6": true
  },
  "ecmaFeatures": {
    "arrowFunctions": true,
    "blockBindings": true,
    "classes": true,
    "defaultParameters": true,
    "destructuring": true,
    "forOf": true,
    "generators": true,
    "modules": true,
    "objectLiteralComputedProperties": true,
    "objectLiteralDuplicateProperties": true,
    "objectLiteralShorthandMethods": true,
    "objectLiteralShorthandProperties": true,
    "regexUFlag": true,
    "regexYFlag": true,
    "restParams": true,
    "spread": true,
    "superInFunctions": true,
    "templateStrings": true,
    "unicodeCodePointEscapes": true,
    "globalReturn": true
  },
  "rules": {
    "comma-dangle": [ 2, "never" ],
    "no-console": 1,
    "no-constant-condition": 2,
    "no-control-regex": 2,
    "no-debugger": 1,
    "no-dupe-keys": 2,
    "no-duplicate-case": 2,
    "no-empty-character-class": 2,
    "no-empty": 2,
    "no-extra-boolean-cast": 2,
    "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-unreachable": 2,
    "use-isnan": 2,
    "valid-typeof": 2,

    "accessor-pairs": 2,
    "block-scoped-var": 2,
    "curly": 2,
    "default-case": 2,
    "dot-location": [ 2, "property" ],
    "dot-notation": 2,
    "eqeqeq": [ 2, "smart" ],
    "no-alert": 1,
    "no-caller": 2,
    "no-case-declarations": 2,
    "no-div-regex": 1,
    "no-else-return": 2,
    "no-eval": 2,
    "no-extend-native": 2,
    "no-extra-bind": 2,
    "no-fallthrough": 2,
    "no-floating-decimal": 2,
    "no-implied-eval": 2,
    "no-iterator": 2,
    "no-labels": 2,
    "no-lone-blocks": 2,
    "no-loop-func": 2,
    "no-multi-spaces": 2,
    "no-multi-str": 2,
    "no-native-reassign": 2,
    "no-new-func": 2,
    "no-new-wrappers": 2,
    "no-new": 2,
    "no-octal-escape": 2,
    "no-octal": 2,
    "no-param-reassign": 2,
    "no-proto": 2,
    "no-redeclare": 2,
    "no-return-assign": 2,
    "no-self-compare": 2,
    "no-throw-literal": 2,
    "no-unused-expressions": [ 2, { "allowShortCircuit": true } ],
    "no-useless-call": 2,
    "no-useless-concat": 2,
    "no-void": 2,
    "no-warning-comments": 1,
    "no-with": 2,
    "radix": [ 2, "as-needed" ],
    "vars-on-top": 2,
    "wrap-iife": [ 2, "inside" ],
    "yoda": 2,

    "strict": [ 2, "function" ],

    "no-catch-shadow": 2,
    "no-delete-var": 2,
    "no-shadow-restricted-names": 2,
    "no-shadow": 2,
    "no-undef-init": 2,
    "no-unused-vars": 2,
    "no-use-before-define": 2,

    "global-require": 2,
    "handle-callback-err": 1,
    "no-new-require": 2,

    "array-bracket-spacing": [ 2, "always" ],
    "block-spacing": [ 2, "always" ],
    "brace-style": [ 2, "1tbs", { "allowSingleLine": false } ],
    "camelcase": [ 2, { "properties": "always" } ],
    "comma-spacing": [ 2, { "before": false, "after": true } ],
    "comma-style": [ 2, "last" ],
    "computed-property-spacing": [ 2, "always" ],
    "consistent-this": [ 2, "self" ],
    "eol-last": 2,
    "func-style": [ 2, "expression" ],
    "indent": [ 2, 4, { "SwitchCase": 1 } ],
    "key-spacing": [ 2, { "beforeColon": false, "afterColon": true } ],
    "new-cap": 2,
    "new-parens": 2,
    "newline-after-var": [ 2, "always" ],
    "no-array-constructor": 2,
    "no-bitwise": 2,
    "no-continue": 2,
    "no-lonely-if": 2,
    "no-mixed-spaces-and-tabs": 2,
    "no-multiple-empty-lines": [ 2, { "max": 2, "maxEOF": 1 } ],
    "no-nested-ternary": 2,
    "no-new-object": 2,
    "no-spaced-func": 2,
    "no-trailing-spaces": [ 2, { "skipBlankLines": true } ],
    "no-unneeded-ternary": 2,
    "object-curly-spacing": [ 2, "always" ],
    "one-var": [ 2, "always" ],
    "operator-linebreak": [ 2, "none" ],
    "quote-props": [ 2, "always" ],
    "quotes": [ 2, "double", "avoid-escape" ],
    "semi": [ 2, "always" ],
    "space-after-keywords": [ 2, "always" ],
    "space-before-blocks": [ 2, "always" ],
    "space-before-function-paren": [ 2, "never" ],
    "space-before-keywords": [ 2, "always" ],
    "space-in-parens": [ 2, "always" ],
    "space-infix-ops": 2,
    "space-return-throw-case": 2,
    "space-unary-ops": [ 2, { "words": true, "nonwords": false } ],
    "spaced-comment": [ 2, "always" ],

    "arrow-parens": [ 2, "always" ],
    "arrow-spacing": 2,
    "constructor-super": 2,
    "generator-star-spacing": [ 2, { "before": true, "after": false } ],
    "no-arrow-condition": 1,
    "no-class-assign": 2,
    "no-const-assign": 2,
    "no-dupe-class-members": 2,
    "no-this-before-super": 2,
    "no-var": 2,
    "prefer-arrow-callback": 1,
    "prefer-spread": 1,
    "prefer-template": 1,
    "require-yield": 2
  }
}

Errors

1. TypeError: Key "rules": Key "space-before-keywords": Rule "space-before-keywords" was removed and replaced by "keyword-spacing".
2. TypeError: Key "rules": Key "space-return-throw-case": Rule "space-return-throw-case" was removed and replaced by "keyword-spacing".
3. TypeError: Key "rules": Key "no-arrow-condition": Rule "no-arrow-condition" was removed and replaced by "no-confusing-arrow,no-constant-condition".

Solution:

"keyword-spacing": ["error", { "before": true }],