.eslintrc.json

{
  "parser": "@babel/eslint-parser",
  "parserOptions": {
    "requireConfigFile": false,
    "babelOptions": {
      "parserOpts": {
        "plugins": ["classProperties", ["decorators", { "decoratorsBeforeExport": false }]]
      }
    }
  },
  "ignorePatterns": ["**/*.html", "**/*.css", "**/*js-meta.xml", "**/*.json"],
  "plugins": ["@lwc/eslint-plugin-lwc"],
  "rules": {
    "@lwc/lwc/consistent-component-name": "error",
    "@lwc/lwc/no-api-reassignments": "off",
    "@lwc/lwc/no-async-operation": "error",
    "@lwc/lwc/no-attributes-during-construction": "error",
    "@lwc/lwc/no-deprecated": "error",
    "@lwc/lwc/no-document-query": "error",
    "@lwc/lwc/no-dupe-class-members": "error",
    "@lwc/lwc/no-inner-html": "error",
    "@lwc/lwc/no-leading-uppercase-api-name": "error",
    "@lwc/lwc/prefer-custom-event": "error",
    "@lwc/lwc/valid-api": [
      "error",
      {
        "disallowUnderscoreUppercaseMix": true
      }
    ],
    "array-callback-return": "error",
    "consistent-return": "error",
    "default-case": "error",
    "dot-notation": "error",
    "eqeqeq": ["error", "smart"],
    "guard-for-in": "error",
    "handle-callback-err": "error",
    "no-alert": "error",
    "no-await-in-loop": "error",
    "no-caller": "error",
    "no-confusing-arrow": "error",
    "no-console": "warn",
    "no-else-return": "error",
    "no-eval": "error",
    "no-extend-native": "error",
    "no-extra-bind": "error",
    "no-implicit-coercion": "error",
    "no-empty-function": [
      "error",
      {
        "allow": ["arrowFunctions", "functions", "methods"]
      }
    ],
    "no-floating-decimal": "error",
    "no-implied-eval": "error",
    "no-iterator": "error",
    "no-label-var": "error",
    "no-labels": "error",
    "no-loop-func": "error",
    "no-multi-str": "error",
    "no-new-func": "error",
    "no-new-object": "error",
    "no-new-wrappers": "error",
    "no-new": "error",
    "no-octal-escape": "error",
    "no-proto": "error",
    "no-return-assign": "error",
    "no-return-await": "error",
    "no-script-url": "error",
    "no-self-compare": "error",
    "no-sequences": "error",
    "no-shadow-restricted-names": "error",
    "no-shadow": "error",
    "no-throw-literal": "error",
    "no-undef-init": "error",
    "no-unused-expressions": "error",
    "no-unused-vars": ["error", { "vars": "all", "args": "after-used" }],
    "no-use-before-define": ["error", { "functions": false }],
    "no-useless-computed-key": "error",
    "no-useless-concat": "error",
    "no-useless-constructor": "error",
    "no-useless-escape": "error",
    "no-useless-rename": "error",
    "no-useless-return": "error",
    "no-void": "error",
    "no-with": "error",
    "radix": "error",
    "vars-on-top": "error",
    "wrap-iife": ["error", "any"]
  }
}