[fix] prerendering always false in global code of hooks.js #4265

.changeset/stale-crabs-carry.md

@@ -0,0 +1,5 @@
+---
+'@sveltejs/kit': patch
+---
+
+load hooks after server initialisation, to ensure `prerendering` is correct

packages/kit/src/core/build/build_server.js

@@ -35,15 +35,6 @@ let read = null;
 
 set_paths(${s(config.kit.paths)});
 
-// this looks redundant, but the indirection allows us to access
-// named imports without triggering Rollup's missing import detection
-const get_hooks = hooks => ({
-	getSession: hooks.getSession || (() => ({})),
-	handle: hooks.handle || (({ event, resolve }) => resolve(event)),
-	handleError: hooks.handleError || (({ error }) => console.error(error.stack)),
-	externalFetch: hooks.externalFetch || fetch
-});
-
 let default_protocol = 'https';
 
 // allow paths to be globally overridden
@@ -57,16 +48,14 @@ export function override(settings) {
 
 export class Server {
 	constructor(manifest) {
-		const hooks = get_hooks(user_hooks);
-
 		this.options = {
 			amp: ${config.kit.amp},
 			csp: ${s(config.kit.csp)},
 			dev: false,
 			floc: ${config.kit.floc},
 			get_stack: error => String(error), // for security
 			handle_error: (error, event) => {
-				hooks.handleError({
+				this.options.hooks.handleError({
 					error,
 					event,
 
@@ -78,7 +67,7 @@ export class Server {
 				});
 				error.stack = this.options.get_stack(error);
 			},
-			hooks,
+			hooks: null,
 			hydrate: ${s(config.kit.browser.hydrate)},
 			manifest,
 			method_override: ${s(config.kit.methodOverride)},
@@ -95,11 +84,21 @@ export class Server {
 		};
 	}
 
-	respond(request, options = {}) {
+	async respond(request, options = {}) {
 		if (!(request instanceof Request)) {
 			throw new Error('The first argument to server.respond must be a Request object. See https://github.com/sveltejs/kit/pull/3384 for details');
 		}
 
+		if (!this.options.hooks) {
+			const module = await import(${s(hooks)});
+			this.options.hooks = {
+				getSession: module.getSession || (() => ({})),
+				handle: module.handle || (({ event, resolve }) => resolve(event)),
+				handleError: module.handleError || (({ error }) => console.error(error.stack)),
+				externalFetch: module.externalFetch || fetch
+			};
+		}
+
 		return respond(request, this.options, options);
 	}
 }

packages/kit/test/prerendering/basics/src/hooks.js

@@ -0,0 +1,15 @@
+import { prerendering } from '$app/env';
+
+const initial_prerendering = prerendering;
+
+export const handle = async ({ event, resolve }) => {
+	if (event.url.pathname === '/prerendering-true' && prerendering) {
+		return await resolve(event, {
+			transformPage: ({ html }) =>
+				html
+					.replace('__INITIAL_PRERENDERING__', initial_prerendering)
+					.replace('__PRERENDERING__', prerendering)
+		});
+	}
+	return await resolve(event);
+};

packages/kit/test/prerendering/basics/src/routes/prerendering-true.svelte

@@ -0,0 +1 @@
+<h1>prerendering: __INITIAL_PRERENDERING__/__PRERENDERING__</h1>

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

@@ -104,4 +104,9 @@ test('decodes paths when writing files', () => {
 	assert.equal(content, JSON.stringify({ path: 'path with encoded spaces' }));
 });
 
+test('prerendering is set to true in global code of hooks.js', () => {
+	const content = read('prerendering-true.html');
+	assert.ok(content.includes('<h1>prerendering: true/true</h1>'), content);
+});
+
 test.run();