correctly determine whether a route uses server data

.changeset/modern-files-watch.md

@@ -0,0 +1,5 @@
+---
+'@sveltejs/kit': patch
+---
+
+Correctly determine whether route uses server data

packages/kit/src/core/sync/write_client_manifest.js

@@ -53,17 +53,13 @@ export function write_client_manifest(manifest_data, output) {
 					while (layouts.at(-1) === '') layouts.pop();
 					while (errors.at(-1) === '') errors.pop();
 
-					/** @type {import('types').RouteData | null} */
-					let current_route = route;
-
 					/** @type {import('types').PageNode | null} */
 					let current_node = route.leaf;
 
 					let uses_server_data = false;
-					while (current_route && !uses_server_data) {
+					while (current_node && !uses_server_data) {
 						uses_server_data = !!current_node?.server;
-						current_route = current_route.parent;
-						current_node = current_route?.layout ?? null;
+						current_node = current_node?.parent ?? null;
 					}
 
 					// encode whether or not the route uses the server data

packages/kit/test/apps/basics/src/routes/load/invalidation/forced/+layout.server.js

@@ -0,0 +1,7 @@
+import { increment } from './state';
+
+export const load = () => {
+	return {
+		a: increment()
+	};
+};

packages/kit/test/apps/basics/src/routes/load/invalidation/forced/+layout.svelte

@@ -0,0 +1 @@
+<slot />

packages/kit/test/apps/basics/src/routes/load/invalidation/forced/+page.server.js

@@ -0,0 +1,7 @@
+import { increment } from './state';
+
+export const load = () => {
+	return {
+		b: increment()
+	};
+};

packages/kit/test/apps/basics/src/routes/load/invalidation/forced/+page.svelte

@@ -0,0 +1,10 @@
+<script>
+	import { invalidate } from '$app/navigation';
+
+	/** @type {import('./$types').PageData} */
+	export let data;
+</script>
+
+<h1>a: {data.a}, b: {data.b}</h1>
+
+<button on:click={() => invalidate()}>invalidate</button>

packages/kit/test/apps/basics/src/routes/load/invalidation/forced/reset/+server.js

@@ -0,0 +1,7 @@
+import { reset } from '../state.js';
+
+/** @type {import('./$types').RequestHandler} */
+export function GET() {
+	reset();
+	return new Response('ok');
+}

packages/kit/test/apps/basics/src/routes/load/invalidation/forced/state.js

@@ -0,0 +1,9 @@
+let count = 0;
+
+export function increment() {
+	return count++;
+}
+
+export function reset() {
+	count = 0;
+}

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

@@ -640,4 +640,24 @@ test.describe.serial('Invalidation', () => {
 		await clicknav('[href="?a=3"]');
 		expect(await page.textContent('h1')).toBe('3');
 	});
+
+	test('server-only load functions are re-run following forced invalidation', async ({
+		page,
+		request
+	}) => {
+		await request.get('/load/invalidation/forced/reset');
+
+		await page.goto('/load/invalidation/forced');
+		expect(await page.textContent('h1')).toBe('a: 0, b: 1');
+
+		await page.click('button');
+		await page.waitForLoadState('networkidle');
+		await page.waitForTimeout(0); // apparently necessary
+		expect(await page.textContent('h1')).toBe('a: 2, b: 3');
+
+		await page.click('button');
+		await page.waitForLoadState('networkidle');
+		await page.waitForTimeout(0);
+		expect(await page.textContent('h1')).toBe('a: 4, b: 5');
+	});
 });