eslint.config.js

import path from 'node:path';
import { fileURLToPath } from 'node:url';

import { FlatCompat } from '@eslint/eslintrc';
import js from '@eslint/js';
import typescriptEslint from '@typescript-eslint/eslint-plugin';
import tsParser from '@typescript-eslint/parser';
import globals from 'globals';
import svelteParser from 'svelte-eslint-parser';

const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);

const compat = new FlatCompat({
  baseDirectory: __dirname,
  recommendedConfig: js.configs.recommended,
  allConfig: js.configs.all,
});

export default [
  {
    ignores: ['**/*.js', '**/playwright.config.ts', '**/service-worker.ts', '.svelte-kit/**'],
  },
  ...compat.extends(
    'eslint:recommended',
    'plugin:@typescript-eslint/recommended',
    'plugin:svelte/recommended',
    'prettier',
  ),
  {
    plugins: {
      '@typescript-eslint': typescriptEslint,
    },

    languageOptions: {
      globals: {
        ...globals.browser,
        ...globals.node,
      },

      parser: tsParser,
      ecmaVersion: 2020,
      sourceType: 'module',

      parserOptions: {
        project: ['tsconfig.json'],
        extraFileExtensions: ['.svelte'],
      },
    },
  },
  {
    files: ['**/*.svelte'],

    languageOptions: {
      parser: svelteParser,
      ecmaVersion: 5,
      sourceType: 'script',

      parserOptions: {
        parser: '@typescript-eslint/parser',
      },
    },

    rules: {
      'svelte/valid-compile': [
        'error',
        {
          ignoreWarnings: true,
        },
      ],
    },
  },
  {
    files: ['**/*.ts', '**/*.svelte'],

    rules: {
      '@typescript-eslint/ban-ts-comment': 'off',
      '@typescript-eslint/no-empty-function': 'off',
      '@typescript-eslint/no-inferrable-types': 'off',
      '@typescript-eslint/no-unused-vars': 'warn',
      '@typescript-eslint/no-misused-promises': 'warn',
      '@typescript-eslint/no-floating-promises': 'warn',
      '@typescript-eslint/no-non-null-assertion': 'warn',

      'no-console': [
        'warn',
        {
          allow: ['warn', 'error'],
        },
      ],
    },
  },
];