chore: robustify some scripts (#17491)

* chore: robustify some scripts

- make it possible to call them with any cwd
- add ability to create test while downloading playground

* use parseArgs

---------

Co-authored-by: Rich Harris <rich.harris@vercel.com>

playgrounds/sandbox/scripts/create-test.js

@@ -1,6 +1,16 @@
-// Creates a test from the existing playground. cwd needs to be playground/sandbox
+// Creates a test from the existing playground. Can be called from anywhere.
 import fs from 'fs';
 import path from 'path';
+import { fileURLToPath } from 'url';
+
+// Get the directory where this script is located
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = path.dirname(__filename);
+
+// Base paths relative to this script's location
+const sandbox_dir = path.resolve(__dirname, '..');
+const src_dir = path.join(sandbox_dir, 'src');
+const tests_dir = path.resolve(__dirname, '../../../packages/svelte/tests');
 
 // Get target folder from command line arguments
 let target_folder = process.argv[2];
@@ -20,7 +30,7 @@ if (!target_folder.startsWith('runtime-')) {
 	process.exit(1);
 }
 target_folder = path.join(
-	path.resolve('../../packages/svelte/tests', target_folder.split('/')[0]),
+	path.resolve(tests_dir, target_folder.split('/')[0]),
 	'samples',
 	target_folder.split('/')[1]
 );
@@ -56,8 +66,8 @@ if (exists) {
 	const files = fs.readdirSync(target_folder);
 	for (const file of files) {
 		if (file !== '_config.js') {
-			const filePath = path.join(target_folder, file);
-			fs.rmSync(filePath, { recursive: true, force: true });
+			const file_path = path.join(target_folder, file);
+			fs.rmSync(file_path, { recursive: true, force: true });
 		}
 	}
 } else {
@@ -65,7 +75,7 @@ if (exists) {
 }
 
 // Starting file
-const app_svelte_path = path.resolve('./src/App.svelte');
+const app_svelte_path = path.join(src_dir, 'App.svelte');
 const collected_files = new Set();
 const processed_files = new Set();
 
@@ -117,7 +127,7 @@ collect_imports(app_svelte_path);
 
 // Copy collected files to target folder
 for (const file_path of collected_files) {
-	const relative_path = path.relative(path.resolve('./src'), file_path);
+	const relative_path = path.relative(src_dir, file_path);
 	let target_path = path.join(target_folder, relative_path);
 
 	// Rename App.svelte to main.svelte

playgrounds/sandbox/scripts/download.js

@@ -1,19 +1,36 @@
 import fs from 'node:fs';
+import path from 'node:path';
+import { parseArgs } from 'node:util';
 
-const arg = process.argv[2];
+const { values, positionals } = parseArgs({
+	options: {
+		'create-test': {
+			type: 'string'
+		}
+	},
+	allowPositionals: true
+});
+
+const create_test_name = values['create-test'] ?? null;
+const url_arg = positionals[0];
+
+if (!url_arg) {
+	console.error(`Missing URL argument`);
+	process.exit(1);
+}
 
 /** @type {URL} */
 let url;
 
 try {
-	url = new URL(arg);
+	url = new URL(url_arg);
 } catch (e) {
-	console.error(`${arg} is not a URL`);
+	console.error(`${url_arg} is not a URL`);
 	process.exit(1);
 }
 
 if (url.origin !== 'https://svelte.dev' || !url.pathname.startsWith('/playground/')) {
-	console.error(`${arg} is not a Svelte playground URL`);
+	console.error(`${url_arg} is not a Svelte playground URL`);
 	process.exit(1);
 }
 
@@ -47,6 +64,55 @@ if (url.hash.length > 1) {
 	});
 }
 
-for (const file of files) {
-	fs.writeFileSync(`src/${file.name}`, file.contents);
+const base_dir = import.meta.dirname;
+
+if (create_test_name) {
+	const test_parts = create_test_name.split('/').filter(Boolean);
+
+	if (test_parts.length > 2) {
+		console.error(
+			`Invalid test name "${create_test_name}". Expected e.g. "hello-world" or "runtime-legacy/hello-world"`
+		);
+		process.exit(1);
+	}
+
+	const suite_name = test_parts.length === 2 ? test_parts[0] : 'runtime-runes';
+	const test_name = test_parts[test_parts.length - 1];
+
+	const output_dir = path.join(
+		base_dir,
+		'../../..',
+		'packages/svelte/tests',
+		suite_name,
+		'samples',
+		test_name
+	);
+	if (fs.existsSync(output_dir)) {
+		console.warn(`Test folder "${output_dir}" already exists, overriding its contents`);
+		fs.rmSync(output_dir, { recursive: true, force: true });
+	}
+	fs.mkdirSync(output_dir, { recursive: true });
+
+	for (const file of files) {
+		const output_name = file.name === 'App.svelte' ? 'main.svelte' : file.name;
+		const output_path = path.join(output_dir, output_name);
+
+		fs.mkdirSync(path.dirname(output_path), { recursive: true });
+		fs.writeFileSync(output_path, file.contents);
+	}
+
+	fs.writeFileSync(
+		path.join(output_dir, '_config.js'),
+		`import { test } from '../../test';
+
+export default test({
+	async test({ assert, target }) {
+	}
+});
+`
+	);
+} else {
+	for (const file of files) {
+		fs.writeFileSync(path.join(base_dir, '..', 'src', file.name), file.contents);
+	}
 }