handle error without message

packages/migrate/migrations/routes/migrate_page_js/index.js

@@ -85,10 +85,16 @@ export function migrate_page(content, filename) {
 						if (nodes.error) {
 							const message = is_string_like(nodes.error)
 								? nodes.error.getText()
-								: is_new(nodes.error, 'Error') && nodes.error.arguments[0].getText();
-
-							if (message) {
-								automigration(node, file.code, `throw error(${status || 500}, ${message});`);
+								: is_new(nodes.error, 'Error')
+								? /** @type {string | undefined} */ (nodes.error.arguments[0]?.getText())
+								: false;
+
+							if (message !== false) {
+								automigration(
+									node,
+									file.code,
+									`throw error(${status || 500}${message ? `, ${message}` : ''});`
+								);
 								imports.add('error');
 								return;
 							}

packages/migrate/migrations/routes/migrate_page_js/samples.md

@@ -157,6 +157,29 @@ export function load({ session }) {
 }
 ```
 
+## Error constructor with no arguments
+
+```js before
+export function load({ session }) {
+	if (!session.user?.admin) {
+		return {
+			status: 403,
+			error: new Error()
+		};
+	}
+}
+```
+
+```js after
+import { error } from '@sveltejs/kit';
+
+export function load({ session }) {
+	if (!session.user?.admin) {
+		throw error(403);
+	}
+}
+```
+
 ## Error status with no error
 
 ```js before