chore: upgrade to eslint v9

also bump all dependencies

eslint.config.mjs

@@ -0,0 +1,258 @@
+/**********************************************************************
+ * Copyright (C) 2024 Red Hat, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ ***********************************************************************/
+
+import globals from 'globals';
+import js from '@eslint/js';
+import typescriptLint from 'typescript-eslint';
+import tsParser from '@typescript-eslint/parser';
+import svelteParser from 'svelte-eslint-parser';
+import importPlugin from 'eslint-plugin-import';
+import { fixupConfigRules, fixupPluginRules } from '@eslint/compat';
+import { fileURLToPath } from 'node:url';
+import path from 'node:path';
+import { FlatCompat } from '@eslint/eslintrc';
+import unicorn from 'eslint-plugin-unicorn';
+import noNull from 'eslint-plugin-no-null';
+import sonarjs from 'eslint-plugin-sonarjs';
+import etc from 'eslint-plugin-etc';
+import svelte from 'eslint-plugin-svelte';
+import redundantUndefined from 'eslint-plugin-redundant-undefined';
+import simpleImportSort from 'eslint-plugin-simple-import-sort';
+
+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,
+});
+
+const TYPESCRIPT_PROJECTS = ['packages/*/tsconfig.json', 'tests/*/tsconfig.json'];
+
+export default [
+  {
+    ignores: [
+      '*.config.*js',
+      '**/*.config.*js',
+      '**/dist/**/*',
+      '**/test-resources',
+      '**/__mocks__/',
+      '**/coverage/',
+      'packages/backend/media/**',
+      '**/.svelte-kit/',
+      'scripts/**',
+      '**/src-generated/',
+    ],
+  },
+  js.configs.recommended,
+  ...typescriptLint.configs.recommended,
+  sonarjs.configs.recommended,
+  ...svelte.configs['flat/recommended'],
+  ...fixupConfigRules(
+    compat.extends('plugin:import/recommended', 'plugin:import/typescript', 'plugin:etc/recommended'),
+  ),
+  {
+    plugins: {
+      // compliant v9 plug-ins
+      unicorn,
+      // non-compliant v9 plug-ins
+      etc: fixupPluginRules(etc),
+      import: fixupPluginRules(importPlugin),
+      'no-null': fixupPluginRules(noNull),
+      'redundant-undefined': fixupPluginRules(redundantUndefined),
+      'simple-import-sort': fixupPluginRules(simpleImportSort),
+    },
+    settings: {
+      'import/resolver': {
+        typescript: true,
+        node: true,
+
+        'eslint-import-resolver-custom-alias': {
+          alias: {
+            '/@': './src',
+            '/@gen': './src-generated',
+          },
+
+          extensions: ['.ts'],
+          packages: ['packages/*'],
+        },
+      },
+    },
+  },
+  {
+    linterOptions: {
+      reportUnusedDisableDirectives: 'off',
+    },
+    languageOptions: {
+      globals: {
+        ...globals.node,
+      },
+      // parser: tsParser,
+      sourceType: 'module',
+      parserOptions: {
+        extraFileExtensions: ['.svelte'],
+        warnOnUnsupportedTypeScriptVersion: false,
+        project: TYPESCRIPT_PROJECTS,
+      },
+    },
+  },
+  {
+    rules: {
+      eqeqeq: 'error',
+      'prefer-promise-reject-errors': 'error',
+      semi: ['error', 'always'],
+      'comma-dangle': ['warn', 'always-multiline'],
+
+      quotes: [
+        'error',
+        'single',
+        {
+          allowTemplateLiterals: true,
+        },
+      ],
+
+      '@typescript-eslint/explicit-function-return-type': 'off',
+      '@typescript-eslint/no-unused-vars': ['error', { argsIgnorePattern: '^_', caughtErrors: 'none' }],
+      '@typescript-eslint/no-var-requires': 'off',
+      '@typescript-eslint/consistent-type-imports': 'error',
+      '@typescript-eslint/no-explicit-any': 'error',
+      '@typescript-eslint/await-thenable': 'error',
+      '@typescript-eslint/no-floating-promises': ['error', { ignoreVoid: false }],
+      '@typescript-eslint/no-misused-promises': 'error',
+      '@typescript-eslint/prefer-optional-chain': 'error',
+      '@typescript-eslint/explicit-function-return-type': 'error',
+      '@typescript-eslint/prefer-nullish-coalescing': [
+        'error',
+        {
+          ignoreConditionalTests: true,
+        },
+      ],
+      '@typescript-eslint/no-require-imports': 'off',
+
+      // unicorn custom rules
+      'unicorn/prefer-node-protocol': 'error',
+
+      'no-null/no-null': 'error',
+      'sonarjs/no-empty-function': 'off',
+      'sonarjs/deprecation': 'off',
+      'sonarjs/todo-tag': 'off',
+      'sonarjs/sonar-no-fallthrough': 'off',
+
+      /**
+       * Having a semicolon helps the optimizer interpret your code correctly.
+       * This avoids rare errors in optimized code.
+       * @see https://twitter.com/alex_kozack/status/1364210394328408066
+       */
+      semi: ['error', 'always'],
+      /**
+       * This will make the history of changes in the hit a little cleaner
+       */
+      'comma-dangle': ['warn', 'always-multiline'],
+      /**
+       * Just for beauty
+       */
+      quotes: ['error', 'single', { allowTemplateLiterals: true }],
+
+      // disabled import/namespace rule as the plug-in is not fully compatible using the compat mode
+      'import/namespace': 'off',
+      'import/no-duplicates': 'error',
+      'import/first': 'error',
+      'import/newline-after-import': 'error',
+      'import/no-extraneous-dependencies': 'error',
+      'import/no-unresolved': 'off',
+      'import/default': 'off',
+      'import/no-named-as-default-member': 'off',
+      'import/no-named-as-default': 'off',
+      'sonarjs/cognitive-complexity': 'off',
+      'sonarjs/no-duplicate-string': 'off',
+      'sonarjs/no-empty-collection': 'off',
+      'sonarjs/no-small-switch': 'off',
+      'etc/no-commented-out-code': 'error',
+      'etc/no-deprecated': 'off',
+      'etc/no-commented-out-code': 'off',
+      'redundant-undefined/redundant-undefined': 'error',
+      'import/no-extraneous-dependencies': 'error',
+      'import/no-restricted-paths': [
+        'error',
+        {
+          zones: [
+            {
+              target: './packages/backend/**/*',
+              from: ['./packages/frontend/**/*'],
+            },
+            {
+              target: './packages/frontend/**/*',
+              from: ['./packages/backend/**/*'],
+            },
+          ],
+        },
+      ],
+
+      // disabled as code in this project is not yet compliant:
+      '@typescript-eslint/explicit-function-return-type': 'off',
+      '@typescript-eslint/no-floating-promises': 'off',
+      '@typescript-eslint/no-explicit-any': 'off',
+      '@typescript-eslint/prefer-nullish-coalescing': 'off',
+      '@typescript-eslint/no-empty-object-type': 'off',
+      'import/newline-after-import': 'off',
+      'unicorn/prefer-node-protocol': 'off',
+      'svelte/valid-compile': 'off',
+      'import/no-extraneous-dependencies': 'off',
+      'import/first': 'off',
+      'no-undef': 'off',
+    },
+  },
+
+  {
+    files: ['**/*.svelte'],
+
+    languageOptions: {
+      parser: svelteParser,
+      ecmaVersion: 5,
+      sourceType: 'script',
+      parserOptions: {
+        parser: tsParser,
+      },
+    },
+
+    rules: {
+      eqeqeq: 'off',
+      'etc/no-implicit-any-catch': 'off',
+      'no-inner-declarations': 'off',
+      'sonarjs/code-eval': 'off',
+      'sonarjs/different-types-comparison': 'off',
+      'sonarjs/prefer-nullish-coalescing': 'off',
+      'sonarjs/no-unused-expressions': 'off',
+      'sonarjs/no-nested-template-literals': 'off',
+      'sonarjs/no-nested-conditional': 'off',
+      '@typescript-eslint/no-unused-vars': 'off',
+      '@typescript-eslint/ban-types': 'off',
+      '@typescript-eslint/no-unused-expressions': 'off',
+    },
+  },
+
+  {
+    files: ['packages/frontend/**'],
+    languageOptions: {
+      globals: {
+        ...Object.fromEntries(Object.entries(globals.node).map(([key]) => [key, 'off'])),
+        ...globals.browser,
+      },
+    },
+  },
+];