.eslintrc.json

{
  "root":true,
  "extends": [
    "eslint:recommended",
    "google",
    "plugin:cypress/recommended",
    "plugin:wc/recommended",
    "plugin:lit/recommended"
  ],
  "parser": "babel-eslint",
  "parserOptions": {
    "ecmaVersion": 6,
    "sourceType": "module"
  },
  "env": {
    "browser": true,
    "es6": true
  },
  // "eslintIgnore": ["cypress.config.js"],
  // "ignorePatterns": ["cypress.config.js","cypress"],
  "rules": {
    "indent": ["error", 4, {
      "SwitchCase": 1,
      "ignoredNodes": ["TemplateLiteral","TaggedTemplateExpression","ObjectExpression","ArrowFunctionExpression"]
      }
    ],
    "no-multiple-empty-lines":["error",{"max":1}],
    "max-len": ["error", 230],
    "no-console": ["error", { "allow": ["log", "warn", "error", "time", "timeEnd"] }],
    "no-param-reassign": ["warn", { "props": true }],
    "no-undef": ["warn"],
    "no-underscore-dangle": [0, { "allowAfterThis": true }],
    "no-unused-vars": ["warn", { "varsIgnorePattern": "^[A-Za-z]+$" }],
    "no-use-before-define": ["error", { "classes": false }],
    "padded-blocks": ["error", { "classes": "always" }],
    "quotes": ["warn", "double", {"allowTemplateLiterals": true}],
    "comma-dangle": ["error", "only-multiline"],
    "arrow-parens": ["error","as-needed"],
    "no-invalid-this": 0,
    "babel/no-invalid-this": 0,
    "object-curly-spacing": ["error", "never"],
    "valid-jsdoc": [2, {"prefer": {"return": "returns"}}],
    "require-jsdoc": 0,
    "space-before-function-paren": ["error", {
      "anonymous": "always",
      "named": "never",
      "asyncArrow": "always"
    }],
    "keyword-spacing": "error",
    "space-in-parens": ["error", "never"],
    "no-case-declarations": 0,
    "one-var":  ["error", { "initialized": "never", "uninitialized": "always" }]
  },
  "plugins": [
    "lit"
  ],
  "overrides": [
    {
      "files": ["*.js"],
      "rules": {
        "lit/no-property-change-update": 0,
        "cypress/no-unnecessary-waiting": 0
      }
    }
  ],
  "globals": {
    "$": true,
    "globalThis": true
  }
}