.eslintrc.js

// eslint-disable-next-line functional/immutable-data
module.exports = {
  parser: '@typescript-eslint/parser',
  extends: [
    'plugin:@typescript-eslint/recommended',
    'plugin:jsx-a11y/recommended',
    'plugin:astro/recommended',
    'preact',
  ],
  plugins: ['functional'],
  rules: {
    'react/prop-types': 0,
    '@typescript-eslint/explicit-function-return-type': 0,
    '@typescript-eslint/explicit-module-boundary-types': 0,
    'functional/no-let': 0,
    'functional/prefer-readonly-type': 0,
    'functional/no-method-signature': 0,
    'no-var': 'error',
    'no-param-reassign': 'error',
    'prefer-const': 'error',
  },
  overrides: [
    {
      // Define the configuration for `.astro` file.
      files: ['*.astro'],
      // Allows Astro components to be parsed.
      parser: 'astro-eslint-parser',
      // Parse the script in `.astro` as TypeScript by adding the following configuration.
      // It's the setting you need when using TypeScript.
      parserOptions: {
        parser: '@typescript-eslint/parser',
        extraFileExtensions: ['.astro'],
      },
      rules: {
        // override/add rules settings here, such as:
        // "astro/no-set-html-directive": "error"
      },
    },
    // ...
  ],
  parserOptions: {
    ecmaFeatures: {
      jsx: true,
    },
  },
  settings: {
    react: {
      version: 'detect',
    },
  },
};