.eslintrc.json

{
  "env": {
    "commonjs": true,
    "es6": true,
    "node": true,
    "browser": true
  },
  "parser": "@babel/eslint-parser",
  "parserOptions": {
    "ecmaVersion": 2020,
    "sourceType": "module"
  },
  "extends": ["plugin:node/recommended"],
  "plugins": ["prettier", "mocha-no-only", "node"],
  "rules": {
    "prettier/prettier": ["warn"],
    "no-warning-comments": [
      "warn",
      {"terms": ["fixme", "removeme", "xxx", "@@@"], "location": "anywhere"}
    ],
    "no-process-exit": "off",
    "no-const-assign": "error",
    "no-this-before-super": "error",
    "no-undef": "warn",
    "no-unreachable": "warn",
    "no-unused-vars": [
      "warn",
      {"varsIgnorePattern": "^_", "args": "all", "argsIgnorePattern": "^_"}
    ],
    "constructor-super": "warn",
    "valid-typeof": "warn",
    "mocha-no-only/mocha-no-only": "warn",
    "node/no-unsupported-features/es-syntax": ["error", {
      "ignores": ["dynamicImport", "modules"]
    }],
    "node/exports-style": ["error", "module.exports"]
  }
}