chore(deps): update to eslint v9 (#927)

* chore(deps): update to eslint v9

* wip: refactor to add svelte/eslint-config and remove compat layer

* fixes

* fix: ignore missing import that isn't needed if not built

* remove things that have no effect or are defined in svelte_config already

* fix: add missing peer for svelte eslint config

* chore: remove empty lines

* chore: cleanup eslint config

* chore: reduce eslint config more

* chore: update to latest svelte eslint setup

* chore: more explicit name for org config, remove declaration for markdown thats already included in recommended config

Author: dominikg

.eslintrc.cjs

@@ -23,7 +23,8 @@ export default {
 				'**/pnpm-lock.yaml',
 				'.changeset/pre.json',
 				'**/vite.config.js.timestamp-*.mjs',
-				'packages/e2e-tests/dynamic-compile-options/src/components/A.svelte'
+				'packages/e2e-tests/dynamic-compile-options/src/components/A.svelte',
+				'packages/playground/big/src/pages/**' // lots of generated files
 			],
 			options: {
 				rangeEnd: 0

.prettierrc.js

@@ -0,0 +1,162 @@
+import markdown from 'eslint-plugin-markdown';
+import globals from 'globals';
+import n from 'eslint-plugin-n';
+import svelteOrgEslintConfig from '@sveltejs/eslint-config';
+import svelteParser from 'svelte-eslint-parser';
+export default [
+	{
+		name: 'local/ignores',
+		ignores: [
+			'**/temp/**',
+			'**/dist/**',
+			'**/build/**',
+			'**/.svelte-kit/**',
+			'**/.svelte/**',
+			'packages/playground/big/src/pages/**', // lots of generated files
+			'packages/*/types/index.d.ts',
+			'packages/*/types/index.d.ts.map',
+			'packages/*/CHANGELOG.md'
+		]
+	},
+	...svelteOrgEslintConfig, // contains setup for svelte, typescript and unicorn
+	n.configs['flat/recommended-module'],
+	...markdown.configs.recommended,
+	{
+		name: 'local/language-options',
+		languageOptions: {
+			ecmaVersion: 2022,
+			sourceType: 'module'
+		}
+	},
+	{
+		name: 'local/generic-rules',
+		rules: {
+			'n/no-unsupported-features/es-builtins': 'error',
+			'n/no-unsupported-features/es-syntax': 'error',
+			'no-console': 'off',
+			'no-debugger': 'error',
+
+			'n/no-extraneous-import': [
+				'error',
+				{
+					allowModules: ['vite', 'vitest']
+				}
+			],
+
+			'no-restricted-properties': [
+				'error',
+				{
+					property: 'substr',
+					message: 'Use .slice instead of .substr.'
+				}
+			],
+
+			'n/no-unpublished-import': 'off',
+			'n/no-unpublished-require': 'off',
+			'no-process-exit': 'off',
+
+			'prefer-const': [
+				'error',
+				{
+					destructuring: 'all'
+				}
+			],
+
+			quotes: [
+				'error',
+				'single',
+				{
+					avoidEscape: true
+				}
+			],
+
+			'unicorn/prefer-node-protocol': 'error'
+		}
+	},
+	{
+		name: 'local/packages-src',
+		files: ['packages/*/src/**'],
+		rules: {
+			'no-console': 'error'
+		}
+	},
+	{
+		name: 'local/inspector-extras',
+		files: [
+			'packages/vite-plugin-svelte-inspector/src/runtime/load-inspector.js',
+			'packages/vite-plugin-svelte-inspector/src/runtime/Inspector.svelte'
+		],
+
+		languageOptions: {
+			globals: {
+				...globals.browser
+			}
+		},
+		rules: {
+			'n/no-unsupported-features/node-builtins': 'off'
+		}
+	},
+	{
+		name: 'local/tests-and-playground-rules',
+		files: ['packages/e2e-tests/**', 'packages/playground/**'],
+
+		rules: {
+			'n/no-extraneous-import': 'off'
+		}
+	},
+	{
+		name: 'local/svelte-files',
+		files: ['**/*.svelte'],
+
+		languageOptions: {
+			globals: {
+				...globals.browser
+			},
+			parserOptions: {
+				parser: '@typescript-eslint/parser'
+			}
+		},
+
+		rules: {
+			'n/no-missing-import': 'off' // n doesn't know some vite specifics or monorepo imports.
+		}
+	},
+	{
+		name: 'local/svelte-runes-globals',
+		files: ['**/*.svelte.js', '**/*.svelte.ts', '**/*.svelte.*.js', '**/*.svelte.*.ts'],
+		languageOptions: {
+			parser: svelteParser
+		}
+	},
+	{
+		name: 'local/markdown-codefences',
+		files: ['**/*.md/*.js', '**/*.md/*.ts', '**/*.md/*.svelte'],
+		rules: {
+			'n/no-missing-import': 'off',
+			'@typescript-eslint/no-unused-vars': 'off'
+		}
+	},
+	{
+		name: 'local/spec-files',
+		files: ['**/__tests__/**/*.spec.ts'],
+
+		languageOptions: {
+			globals: {
+				...globals.jest,
+				...globals.node,
+				...globals.browser
+			}
+		},
+		rules: {
+			'n/no-missing-import': 'off'
+		}
+	},
+	{
+		name: 'local/allow-unused-vars',
+		files: ['**/vite.config.*', 'packages/e2e-tests/**', '**/*.d.ts'],
+		rules: {
+			'no-unused-vars': 'off',
+			'@typescript-eslint/no-unused-vars': 'off'
+		}
+	}
+];