chore: make filename an options object to futureproof it

packages/svelte/src/compiler/migrate/index.js

@@ -27,10 +27,10 @@ const style_placeholder = '/*$$__STYLE_CONTENT__$$*/';
  * May throw an error if the code is too complex to migrate automatically.
  *
  * @param {string} source
- * @param {string} [filename]
+ * @param {{filename?: string}} [options]
  * @returns {{ code: string; }}
  */
-export function migrate(source, filename) {
+export function migrate(source, { filename } = {}) {
 	try {
 		// Blank CSS, could contain SCSS or similar that needs a preprocessor.
 		// Since we don't care about CSS in this migration, we'll just ignore it.

packages/svelte/tests/migrate/test.ts

@@ -14,7 +14,9 @@ const { test, run } = suite<ParserTest>(async (config, cwd) => {
 		.replace(/\s+$/, '')
 		.replace(/\r/g, '');
 
-	const actual = migrate(input, config.skip_filename ? undefined : `${cwd}/output.svelte`).code;
+	const actual = migrate(input, {
+		filename: config.skip_filename ? undefined : `${cwd}/output.svelte`
+	}).code;
 
 	// run `UPDATE_SNAPSHOTS=true pnpm test migrate` to update parser tests
 	if (process.env.UPDATE_SNAPSHOTS || !fs.existsSync(`${cwd}/output.svelte`)) {

sites/svelte-5-preview/src/lib/workers/compiler/index.js

@@ -135,7 +135,7 @@ function compile({ id, source, options, return_ast }) {
 /** @param {import("../workers").MigrateMessageData} param0 */
 function migrate({ id, source, filename }) {
 	try {
-		const result = svelte.migrate(source, filename);
+		const result = svelte.migrate(source, { filename });
 
 		return {
 			id,