recreating the project, but without experimental Svelte 5 support

eslint.config.js

@@ -0,0 +1,23 @@
+import js from '@eslint/js';
+import svelte from 'eslint-plugin-svelte';
+import prettier from 'eslint-config-prettier';
+import globals from 'globals';
+
+/** @type {import('eslint').Linter.Config[]} */
+export default [
+	js.configs.recommended,
+	...svelte.configs['flat/recommended'],
+	prettier,
+	...svelte.configs['flat/prettier'],
+	{
+		languageOptions: {
+			globals: {
+				...globals.browser,
+				...globals.node
+			}
+		}
+	},
+	{
+		ignores: ['build/', '.svelte-kit/', 'dist/']
+	}
+];

package.json

@@ -6,17 +6,24 @@
 		"dev": "vite dev",
 		"build": "vite build",
 		"preview": "vite preview",
-		"lint": "prettier --check .",
+		"test": "vitest",
+		"lint": "prettier --check . && eslint .",
 		"format": "prettier --write ."
 	},
 	"devDependencies": {
 		"@sveltejs/adapter-auto": "^3.0.0",
 		"@sveltejs/kit": "^2.0.0",
 		"@sveltejs/vite-plugin-svelte": "^3.0.0",
+		"@types/eslint": "^9.6.0",
+		"eslint": "^9.0.0",
+		"eslint-config-prettier": "^9.1.0",
+		"eslint-plugin-svelte": "^2.36.0",
+		"globals": "^15.0.0",
 		"prettier": "^3.1.1",
 		"prettier-plugin-svelte": "^3.1.2",
-		"svelte": "^5.0.0-next.1",
+		"svelte": "^4.2.7",
-		"vite": "^5.0.3"
+		"vite": "^5.0.3",
+		"vitest": "^2.0.0"
 	},
 	"type": "module"
 }

src/index.test.js

@@ -0,0 +1,7 @@
+import { describe, it, expect } from 'vitest';
+
+describe('sum test', () => {
+	it('adds 1 + 2 to equal 3', () => {
+		expect(1 + 2).toBe(3);
+	});
+});

vite.config.js

@@ -1,6 +1,9 @@
 import { sveltekit } from '@sveltejs/kit/vite';
-import { defineConfig } from 'vite';
+import { defineConfig } from 'vitest/config';
 
 export default defineConfig({
-	plugins: [sveltekit()]
+	plugins: [sveltekit()],
+	test: {
+		include: ['src/**/*.{test,spec}.{js,ts}']
+	}
 });