.eslintrc.js

module.exports = {
  parser: "@typescript-eslint/parser",
  plugins: ["@typescript-eslint"],
  extends: [
    "react-app",
    "airbnb-base",
    "plugin:prettier/recommended",
    "plugin:react/recommended",
  ],
  overrides: [
    {
      files: [
        "src/**/*.test.js",
        "src/**/*.test.jsx",
        "src/**/*.test.ts",
        "src/**/*.test.tsx",
      ],
      extends: [
        "plugin:jest/recommended",
        "plugin:jest/style",
        "plugin:testing-library/react",
      ],
      env: {
        jest: true,
      },
    },
    {
      files: ["**/*.ts", "**/*.tsx"],
      extends: ["plugin:@typescript-eslint/recommended"],
    },
  ],
  rules: {
    "linebreak-style": [
      "error",
      process.platform === "win32" ? "windows" : "unix",
    ], // https://stackoverflow.com/q/39114446/2771889
    "import/prefer-default-export": 0, // https://stackoverflow.com/q/54245654/2771889
    "react/sort-comp": "off", // https://github.com/yannickcr/eslint-plugin-react/issues/1214
    "no-restricted-syntax": [
      // Allow `ForOfStatement` but keep other defaults https://github.com/airbnb/javascript/issues/1271#issuecomment-548688952
      "error",
      {
        selector: "ForInStatement",
        message:
          "for..in loops iterate over the entire prototype chain, which is virtually never what you want. Use Object.{keys,values,entries}, and iterate over the resulting array.",
      },
      {
        selector: "LabeledStatement",
        message:
          "Labels are a form of GOTO; using them makes code confusing and hard to maintain and understand.",
      },
      {
        selector: "WithStatement",
        message:
          "`with` is disallowed in strict mode because it makes code impossible to predict and optimize.",
      },
    ],
    "import/no-anonymous-default-export": "error", // https://github.com/c-hive/guides/blob/a82e1b37ef662c8f8d7485793f99970080f40dca/js/best-practices.md#name-functions-when-exporting
    "import/no-extraneous-dependencies": [ // https://stackoverflow.com/q/44939304/2771889
      "error",
      {
        devDependencies: ["**/*.test.ts", "**/*.test.tsx", "src/setupTests.ts"],
      },
    ],
    "import/extensions": [ // https://stackoverflow.com/a/59268871/2771889
      "error",
      "ignorePackages",
      {
        "js": "never",
        "jsx": "never",
        "ts": "never",
        "tsx": "never"
      },
    ],
    "@typescript-eslint/no-unused-vars": [
      "error",
      { varsIgnorePattern: "_", argsIgnorePattern: "_" },
    ],
  },
  env: {
    browser: true,
  },
  settings: {
    react: {
      version: "detect",
    },
    "import/resolver": { // https://stackoverflow.com/a/55280867/2771889
      node: {
        extensions: [".js", ".jsx", ".ts", ".tsx"],
        paths: ["src"],
      },
    },
  },
};