refactor: upgrade ESLint to v9.x

Author: mrholek

.eslintignore

@@ -0,0 +1,128 @@
+import xo from 'eslint-config-xo'
+import xoBrowser from 'eslint-config-xo/browser'
+import eslintPluginImport from 'eslint-plugin-import'
+import eslintPluginUnicorn from 'eslint-plugin-unicorn'
+import globals from 'globals'
+
+export default [
+  eslintPluginImport.flatConfigs.errors,
+  eslintPluginImport.flatConfigs.warnings,
+  eslintPluginUnicorn.configs['flat/recommended'],
+  ...xo,
+  ...xoBrowser,
+  {
+    ignores: [
+      '**/*.min.js',
+      '**/dist/',
+      '.babelrc.js'
+    ]
+  },
+  {
+    rules: {
+      '@stylistic/comma-dangle': 'off',
+      '@stylistic/function-paren-newline': 'off',
+      '@stylistic/indent': 'off',
+      '@stylistic/indent-binary-ops': 'off',
+      '@stylistic/jsx-quotes': 'off',
+      '@stylistic/max-len': 'off',
+      '@stylistic/object-curly-spacing': 'off',
+      '@stylistic/operator-linebreak': 'off',
+      '@stylistic/quotes': 'off',
+      '@stylistic/semi': 'off',
+      'arrow-body-style': 'off',
+      'capitalized-comments': 'off',
+      'comma-dangle': ['error', 'never'],
+      'import/extensions': [
+        'error',
+        'ignorePackages',
+        {
+          js: 'always'
+        }
+      ],
+      'import/first': 'error',
+      'import/newline-after-import': 'error',
+      'import/no-absolute-path': 'error',
+      'import/no-amd': 'error',
+      'import/no-cycle': [
+        'error',
+        {
+          ignoreExternal: true
+        }
+      ],
+      'import/no-duplicates': 'error',
+      'import/no-extraneous-dependencies': 'error',
+      'import/no-mutable-exports': 'error',
+      'import/no-named-as-default': 'error',
+      'import/no-named-as-default-member': 'error',
+      'import/no-named-default': 'error',
+      'import/no-self-import': 'error',
+      'import/no-unassigned-import': ['error'],
+      'import/no-useless-path-segments': 'error',
+      'import/order': 'error',
+      indent: [
+        'error',
+        2,
+        {
+          MemberExpression: 'off',
+          SwitchCase: 1
+        }
+      ],
+      'logical-assignment-operators': 'off',
+      'max-params': ['warn', 5],
+      'multiline-ternary': ['error', 'always-multiline'],
+      'new-cap': [
+        'error',
+        {
+          properties: false
+        }
+      ],
+      'no-console': 'error',
+      'no-negated-condition': 'off',
+      'object-curly-spacing': ['error', 'always'],
+      'operator-linebreak': ['error', 'after'],
+      'prefer-object-has-own': 'off',
+      'prefer-template': 'error',
+      semi: ['error', 'never'],
+      strict: 'error',
+      'unicorn/explicit-length-check': 'off',
+      'unicorn/filename-case': 'off',
+      'unicorn/no-anonymous-default-export': 'off',
+      'unicorn/no-array-callback-reference': 'off',
+      'unicorn/no-array-method-this-argument': 'off',
+      'unicorn/no-null': 'off',
+      'unicorn/no-typeof-undefined': 'off',
+      'unicorn/no-unused-properties': 'error',
+      'unicorn/numeric-separators-style': 'off',
+      'unicorn/prefer-array-flat': 'off',
+      'unicorn/prefer-at': 'off',
+      'unicorn/prefer-dom-node-dataset': 'off',
+      'unicorn/prefer-global-this': 'off', // added to avoid the error: 'Use `globalThis` instead of `window` or `global`'
+      'unicorn/prefer-module': 'off',
+      'unicorn/prefer-query-selector': 'off',
+      'unicorn/prefer-spread': 'off',
+      'unicorn/prefer-string-raw': 'off',
+      'unicorn/prefer-string-replace-all': 'off',
+      'unicorn/prefer-structured-clone': 'off',
+      'unicorn/prevent-abbreviations': 'off'
+    }
+  },
+  {
+    files: ['**/*.{js,mjs}'],
+    languageOptions: {
+      sourceType: 'module'
+    }
+  },
+  {
+    files: ['build/**'],
+    languageOptions: {
+      globals: {
+        ...globals.node
+      },
+      sourceType: 'module'
+    },
+    rules: {
+      'no-console': 'off',
+      'unicorn/prefer-top-level-await': 'off'
+    }
+  }
+]