.eslintrc.json

{
  "parserOptions": {
    "emcmaVersion": 6,
    "sourceType": "module"
  },
  "parser": "esprima",
  "extends": "eslint:recommended",
  "rules": {
    "quotes": ["warn", "single", { "avoidEscape": true }],
    "semi": ["error", "always"],
    "no-duplicate-case": "warn",
    "camelcase": "error",
    "no-var": "error",
    "brace-style": ["warn", "1tbs", { "allowSingleLine": true }],
    "comma-spacing": ["warn", { "before": false, "after": true }],
    "eqeqeq": ["error", "always"],
    "arrow-spacing": "warn",
    "indent": ["warn", 4],
    "no-mixed-spaces-and-tabs": "error",
    "no-multi-spaces": "warn",
    "block-spacing": "warn",
    "no-whitespace-before-property": "error",
    "keyword-spacing": "error",
    "no-async-promise-executor": 0
  },
  "env": {
    "node": true,
    "mocha": true,
    "es6": true,
    "browser": true
  }
}