.eslintrc.js

module.exports = {
  root: true,
  env: {
    browser: true,
    es2021: true,
    node: true,
  },
  extends: [
    "next",
    "eslint:recommended",
    "prettier",
    "plugin:@typescript-eslint/recommended",
  ],
  parser: "@typescript-eslint/parser",
  parserOptions: {
    ecmaVersion: "latest",
    sourceType: "module",
  },
  plugins: [
    "@typescript-eslint",
    "import",
    "simple-import-sort",
    "unused-imports",
  ],
  rules: {
    "@typescript-eslint/no-redeclare": "error",
    "@typescript-eslint/no-unused-vars": [
      "error",
      // Sometimes need to have unused values when object destructuring.
      // Make this an opt-in pattern, so unused `_foo` will be allowed.
      {
        argsIgnorePattern: "^_",
        caughtErrorsIgnorePattern: "^_",
        varsIgnorePattern: "^_",
      },
    ],
    // ESLint base
    "default-case": "warn",
    "default-case-last": "error",
    "default-param-last": "warn",
    "dot-notation": "warn",
    "eqeqeq": "error",
    "import/first": "error",
    "import/newline-after-import": "error",
    "import/no-duplicates": "error",
    "no-console": ["warn", { allow: ["warn", "error"] }],
    "no-eval": "error",
    "no-implicit-coercion": "warn",
    "no-implied-eval": "error",
    "no-invalid-this": "error",
    "no-lone-blocks": "error",
    "no-new-wrappers": "error",
    "no-param-reassign": "error",
    "no-promise-executor-return": "error",
    "no-proto": "error",
    "no-redeclare": "off",
    "no-return-assign": "error",
    "no-return-await": "error",
    "no-self-compare": "error",
    "no-sequences": "warn",
    "no-unneeded-ternary": "warn",
    "no-unused-vars": "off",
    // we use `unused-imports`
    "no-useless-call": "warn",
    "no-useless-catch": "error",
    "no-useless-constructor": "warn",
    "no-useless-escape": "warn",
    "no-useless-rename": "warn",
    "no-var": "error",
    "prefer-arrow-callback": ["warn", { allowNamedFunctions: true }],
    "prefer-const": "warn",
    "prefer-destructuring": "warn",
    "prefer-object-spread": "warn",
    "prefer-promise-reject-errors": "warn",
    "prefer-rest-params": "warn",
    "prefer-spread": "warn",
    "quote-props": ["warn", "consistent-as-needed"],
    "quotes": [
      "warn",
      "double",
      { allowTemplateLiterals: false, avoidEscape: true },
    ],
    // TODO:
    // 'sort-imports': 'warn',
    // 'sort-keys': 'warn',
    // 'sort-vars': 'warn',
    "require-atomic-updates": "error",
    // We have TS for this
    "simple-import-sort/exports": "error",
    "simple-import-sort/imports": "error",
    "yoda": ["warn", "never"],
    // Next
    "@next/next/no-html-link-for-pages": "off",
    "react/no-children-prop": "off",
    "react/prop-types": "off",
    // Yay
    "unused-imports/no-unused-imports": "error",
    "unused-imports/no-unused-vars": [
      "warn",
      {
        args: "after-used",
        argsIgnorePattern: "^_",
        vars: "all",
        varsIgnorePattern: "^_",
      },
    ],
  },
};