Fix missing hook arguments of in-flight requests

CHANGELOG.md

@@ -1,5 +1,10 @@
 # Changelog
 
+## [3.2.12] - 2026-09-03
+
+- Set `args.page` when a navigation reuses an in-flight preload
+- Fall back to a fresh fetch when an in-flight preload fails instead of aborting the visit
+
 ## [3.2.11] - 2024-11-20
 
 - Return cached data or pending promise for `swup.preload()` if already preloaded or preloading
@@ -129,6 +134,7 @@
 
 - Initial release
 
+[3.2.12]: https://github.com/swup/preload-plugin/releases/tag/3.2.12
 [3.2.11]: https://github.com/swup/preload-plugin/releases/tag/3.2.11
 [3.2.10]: https://github.com/swup/preload-plugin/releases/tag/3.2.10
 [3.2.9]: https://github.com/swup/preload-plugin/releases/tag/3.2.9

src/index.ts

@@ -181,12 +181,20 @@ export default class SwupPreloadPlugin extends Plugin {
 	/**
 	 * Before core page load: return existing preload promise if available.
 	 */
-	protected onPageLoad: HookDefaultHandler<'page:load'> = (visit, args, defaultHandler) => {
+	protected onPageLoad: HookDefaultHandler<'page:load'> = async (visit, args, defaultHandler) => {
 		const { url } = visit.to;
-		if (url && this.preloadPromises.has(url)) {
-			return this.preloadPromises.get(url) as Promise<PageData>;
+
+		const preloadPromise = url ? this.preloadPromises.get(url) : undefined;
+
+		// A preload can fail and end up with no page to reuse
+		const page = (await preloadPromise?.catch(() => undefined)) ?? null;
+		if (!page) {
+			return defaultHandler!(visit, args);
 		}
-		return defaultHandler!(visit, args);
+
+		args.page = page;
+		args.cache = false;
+		return page;
 	};
 
 	/**

tests/functional/inc/commands.ts

@@ -16,6 +16,20 @@ export function sleep(timeout = 0): Promise<void> {
 	return new Promise((resolve) => setTimeout(() => resolve(undefined), timeout));
 }
 
+function documentOrigin(page: Page) {
+	return page.evaluate(() => Math.floor(window.performance.timeOrigin));
+}
+
+export async function expectNoPageReload(
+	page: Page,
+	action: (page: Page) => Promise<unknown> | unknown
+) {
+	const before = await documentOrigin(page);
+	await action(page);
+	await sleep(500);
+	expect(await documentOrigin(page)).toEqual(before);
+}
+
 export async function clickOnLink(page: Page, url: string, options?: Parameters<Page['click']>[1]) {
 	await page.click(`a[href="${url}"]`, options);
 	await expectToBeAt(page, url);

tests/functional/preload-plugin.spec.ts

@@ -5,6 +5,7 @@ import {
 	clickOnLink,
 	waitForSwup,
 	navigateWithSwup,
+	expectNoPageReload,
 	expectSwupToHaveCacheEntry,
 	expectSwupNotToHaveCacheEntry,
 	expectSwupToHaveCacheEntries,
@@ -282,3 +283,87 @@ test.describe('ignores external origins', () => {
 		expect(urls).toEqual(['/page-1.html', '/page-2.html']);
 	});
 });
+
+test.describe('page:load args', () => {
+	test.beforeEach(async ({ page }) => {
+		await page.goto('/page-1.html');
+		await waitForSwup(page);
+		await page.evaluate(() => {
+			window._swup.hooks.on('page:load', (visit, args) => {
+				window.data = { page: args.page, cache: args.cache };
+			});
+		});
+	});
+
+	test('provides page data when reusing an in-flight preload', async ({ page }) => {
+		let releasePreload!: () => void;
+		let markRequestStarted!: () => void;
+		const requestStarted = new Promise<void>((resolve) => (markRequestStarted = resolve));
+		const release = new Promise<void>((resolve) => (releasePreload = resolve));
+
+		await page.route('**/page-2.html', async (route) => {
+			markRequestStarted();
+			await release;
+			await route.continue();
+		});
+
+		await page.evaluate(() => {
+			window._swup.preload!('/page-2.html');
+		});
+		await requestStarted;
+		await clickOnLink(page, '/page-2.html');
+		await sleep(500);
+		releasePreload();
+
+		await expect(page.locator('h1')).toHaveText('Page 2', { timeout: 5000 });
+
+		const pageArgs = await page.evaluate(() => window.data);
+		expect(pageArgs.page).toBeTruthy();
+		expect(pageArgs.page.url).toContain('/page-2.html');
+		expect(pageArgs.page.html).toContain('Page 2');
+		expect(pageArgs.cache).toBe(false);
+	});
+
+	test('recovers when a reused in-flight preload fails', async ({ page }) => {
+		let requestCount = 0;
+		let releasePreload!: () => void;
+		let markRequestStarted!: () => void;
+		const requestStarted = new Promise<void>((resolve) => (markRequestStarted = resolve));
+		const release = new Promise<void>((resolve) => (releasePreload = resolve));
+
+		await page.route('**/page-2.html', async (route) => {
+			requestCount++;
+			if (requestCount === 1) {
+				markRequestStarted();
+				await release;
+				await route.abort();
+			} else {
+				await route.continue();
+			}
+		});
+
+		await expectNoPageReload(page, async () => {
+			await page.evaluate(() => {
+				window._swup.preload!('/page-2.html');
+			});
+			await requestStarted;
+			await clickOnLink(page, '/page-2.html');
+			await sleep(500);
+			releasePreload();
+
+			await expect(page.locator('h1')).toHaveText('Page 2', { timeout: 5000 });
+		});
+
+		const pageArgs = await page.evaluate(() => window.data);
+		expect(pageArgs?.page).toBeTruthy();
+	});
+
+	test('provides page data when no preload is in flight', async ({ page }) => {
+		await navigateWithSwup(page, '/page-2.html');
+		await expect(page.locator('h1')).toHaveText('Page 2');
+
+		const pageArgs = await page.evaluate(() => window.data);
+		expect(pageArgs?.page).toBeTruthy();
+		expect(pageArgs.page.url).toContain('/page-2.html');
+	});
+});