fix: crawl hrefs that start with config.prerender.origin (#12277)

.changeset/rude-hairs-roll.md

@@ -0,0 +1,5 @@
+---
+"@sveltejs/kit": patch
+---
+
+fix: hrefs that start with `config.prerender.origin` are now crawled

packages/kit/src/core/postbuild/prerender.js

@@ -276,7 +276,17 @@ async function prerender({ out, manifest_path, metadata, verbose, env }) {
 
 			actual_hashlinks.set(decoded, ids);
 
-			for (const href of hrefs) {
+			/** @param {string} href */
+			const removePrerenderOrigin = (href) => {
+				if (href.startsWith(config.prerender.origin)) {
+					if (href === config.prerender.origin) return '/';
+					if (href.at(config.prerender.origin.length) !== '/') return href;
+					return href.slice(config.prerender.origin.length);
+				}
+				return href;
+			};
+
+			for (const href of hrefs.map(removePrerenderOrigin)) {
 				if (!is_root_relative(href)) continue;
 
 				const { pathname, search, hash } = new URL(href, 'http://localhost');

packages/kit/test/prerendering/basics/src/routes/prerender-origin/+page.svelte

@@ -0,0 +1,6 @@
+<script>
+	import { page } from '$app/stores';
+	const href = new URL('/prerender-origin/dynamic', $page.url.origin).href;
+</script>
+
+<a {href}>Please crawl this</a>

packages/kit/test/prerendering/basics/src/routes/prerender-origin/[dynamic]/+page.svelte

@@ -0,0 +1,4 @@
+<h1>
+	This page will only be discovered if full hrefs that start with config.prerender.origin are
+	crawled
+</h1>

packages/kit/test/prerendering/basics/svelte.config.js

@@ -7,7 +7,7 @@ const config = {
 
 		prerender: {
 			handleHttpError: 'warn',
-			origin: 'http://example.com'
+			origin: 'http://prerender.origin'
 		}
 	}
 };

packages/kit/test/prerendering/basics/test/tests.spec.js

@@ -203,7 +203,7 @@ test('fetches data from local endpoint', () => {
 
 test('respects config.prerender.origin', () => {
 	const content = read('origin.html');
-	expect(content).toMatch('<h2>http://example.com</h2>');
+	expect(content).toMatch('<h2>http://prerender.origin</h2>');
 });
 
 test('$env - includes environment variables', () => {
@@ -253,3 +253,8 @@ test('prerenders paths with optional parameters with empty values', () => {
 	const content = read('optional-params.html');
 	expect(content).includes('Path with Value');
 });
+
+test('crawls links that start with config.prerender.origin', () => {
+	const content = read('prerender-origin/dynamic.html');
+	expect(content).toBeTruthy();
+});