fix: URL instance methods work in load (#5183)

* feat: Failing test

* fix: More surgical approach to replacing url.hash

* feat: Changeset

* create LoadURL class

* use LoadURL on the server as well

Co-authored-by: Rich Harris <hello@rich-harris.dev>

.changeset/popular-pets-obey.md

@@ -0,0 +1,5 @@
+---
+'@sveltejs/kit': patch
+---
+
+[fix] URL instance methods now work in `load`

packages/kit/src/runtime/client/client.js

@@ -2,7 +2,7 @@ import { onMount, tick } from 'svelte';
 import { writable } from 'svelte/store';
 import { coalesce_to_error } from '../../utils/error.js';
 import { normalize } from '../load.js';
-import { normalize_path } from '../../utils/url.js';
+import { LoadURL, normalize_path } from '../../utils/url.js';
 import {
 	create_updated_store,
 	find_anchor,
@@ -527,6 +527,7 @@ export function create_client({ target, session, base, trailing_slash }) {
 		}
 
 		const session = $session;
+		const load_url = new LoadURL(url);
 
 		if (module.load) {
 			/** @type {import('types').LoadEvent} */
@@ -536,18 +537,7 @@ export function create_client({ target, session, base, trailing_slash }) {
 				props: props || {},
 				get url() {
 					node.uses.url = true;
-
-					return new Proxy(url, {
-						get: (target, property) => {
-							if (property === 'hash') {
-								throw new Error(
-									'url.hash is inaccessible from load. Consider accessing hash from the page store within the script tag of your component.'
-								);
-							}
-
-							return Reflect.get(target, property, target);
-						}
-					});
+					return load_url;
 				},
 				get session() {
 					node.uses.session = true;

packages/kit/src/runtime/server/page/load_node.js

@@ -4,6 +4,7 @@ import { normalize } from '../../load.js';
 import { respond } from '../index.js';
 import { is_root_relative, resolve } from '../../../utils/url.js';
 import { create_prerendering_url_proxy } from './utils.js';
+import { LoadURL } from '../../../utils/url.js';
 import { is_pojo, lowercase_keys, normalize_request_method } from '../utils.js';
 import { coalesce_to_error } from '../../../utils/error.js';
 import { domain_matches, path_matches } from './cookie.js';
@@ -84,7 +85,7 @@ export async function load_node({
 	} else if (module.load) {
 		/** @type {import('types').LoadEvent} */
 		const load_input = {
-			url: state.prerendering ? create_prerendering_url_proxy(event.url) : event.url,
+			url: state.prerendering ? create_prerendering_url_proxy(event.url) : new LoadURL(event.url),
 			params: event.params,
 			props: shadow.body || {},
 			routeId: event.routeId,

packages/kit/src/utils/url.js

@@ -52,3 +52,12 @@ export function normalize_path(path, trailing_slash) {
 
 	return path;
 }
+
+export class LoadURL extends URL {
+	/** @returns {string} */
+	get hash() {
+		throw new Error(
+			'url.hash is inaccessible from load. Consider accessing hash from the page store within the script tag of your component.'
+		);
+	}
+}

packages/kit/test/apps/basics/src/routes/load/url-to-string.svelte

@@ -0,0 +1,8 @@
+<script context="module">
+	export const load = ({ url }) => {
+		url.toString();
+		return {};
+	};
+</script>
+
+<h1>I didn't break!</h1>

packages/kit/test/apps/basics/test/test.js

@@ -1516,6 +1516,13 @@ test.describe.parallel('Load', () => {
 		}
 	});
 
+	test('url instance methods work in load', async ({ page, javaScriptEnabled }) => {
+		if (javaScriptEnabled) {
+			await page.goto('/load/url-to-string');
+			expect(await page.textContent('h1')).toBe("I didn't break!");
+		}
+	});
+
 	test('using window.fetch causes a warning', async ({ page, javaScriptEnabled }) => {
 		if (javaScriptEnabled && process.env.DEV) {
 			const warnings = [];