Return 404 status code for 404.astro in SSR (#4247)

* Return 404 status code for 404.astro in SSR

* Adding a changeset

5 files changed, 30 insertions, 8 deletions

diff --git a/.changeset/empty-bottles-allow.md b/.changeset/empty-bottles-allow.md
new file mode 100644
index 000000000..1f6e63d09
--- /dev/null
+++ b/.changeset/empty-bottles-allow.md
@@ -0,0 +1,5 @@
+---
+'astro': patch
+---
+
+Return 404 status code for 404.astro in SSR
diff --git a/packages/astro/src/core/app/index.ts b/packages/astro/src/core/app/index.ts
index fc7aa80bb..fc03d333c 100644
--- a/packages/astro/src/core/app/index.ts
+++ b/packages/astro/src/core/app/index.ts
@@ -82,6 +82,11 @@ export class App {
 			}
 		}
 
+		// Use the 404 status code for 404.astro components
+		if(routeData.route === '/404') {
+			defaultStatus = 404;
+		}
+
 		let mod = this.#manifest.pageMap.get(routeData.component)!;
 
 		if (routeData.type === 'page') {
diff --git a/packages/astro/src/core/app/node.ts b/packages/astro/src/core/app/node.ts
index 17d800b1d..95e47a52c 100644
--- a/packages/astro/src/core/app/node.ts
+++ b/packages/astro/src/core/app/node.ts
@@ -1,9 +1,10 @@
+import type { RouteData } from '../../@types/astro';
 import type { SerializedSSRManifest, SSRManifest } from './types';
 
 import * as fs from 'fs';
 import { IncomingMessage } from 'http';
 import { deserializeManifest } from './common.js';
-import { App } from './index.js';
+import { App, MatchOptions } from './index.js';
 
 const clientAddressSymbol = Symbol.for('astro.clientAddress');
 
@@ -24,10 +25,10 @@ function createRequestFromNodeRequest(req: IncomingMessage, body?: Uint8Array):
 }
 
 export class NodeApp extends App {
-	match(req: IncomingMessage | Request) {
-		return super.match(req instanceof Request ? req : createRequestFromNodeRequest(req));
+	match(req: IncomingMessage | Request, opts: MatchOptions = {}) {
+		return super.match(req instanceof Request ? req : createRequestFromNodeRequest(req), opts);
 	}
-	render(req: IncomingMessage | Request) {
+	render(req: IncomingMessage | Request, routeData?: RouteData) {
 		if ('on' in req) {
 			let body = Buffer.from([]);
 			let reqBodyComplete = new Promise((resolve, reject) => {
@@ -43,10 +44,10 @@ export class NodeApp extends App {
 			});
 
 			return reqBodyComplete.then(() => {
-				return super.render(req instanceof Request ? req : createRequestFromNodeRequest(req, body));
+				return super.render(req instanceof Request ? req : createRequestFromNodeRequest(req, body), routeData);
 			});
 		}
-		return super.render(req instanceof Request ? req : createRequestFromNodeRequest(req));
+		return super.render(req instanceof Request ? req : createRequestFromNodeRequest(req), routeData);
 	}
 }
 
diff --git a/packages/astro/test/ssr-404-500-pages.test.js b/packages/astro/test/ssr-404-500-pages.test.js
index 4f5f1f8cf..1cfc0098c 100644
--- a/packages/astro/test/ssr-404-500-pages.test.js
+++ b/packages/astro/test/ssr-404-500-pages.test.js
@@ -26,6 +26,17 @@ describe('404 and 500 pages', () => {
 		expect($('h1').text()).to.equal('Something went horribly wrong!');
 	});
 
+	it('404 page returned when a route does not match and passing routeData', async () => {
+		const app = await fixture.loadTestAdapterApp();
+		const request = new Request('http://example.com/some/fake/route');
+		const routeData = app.match(request, { matchNotFound: true });
+		const response = await app.render(request, routeData);
+		expect(response.status).to.equal(404);
+		const html = await response.text();
+		const $ = cheerio.load(html);
+		expect($('h1').text()).to.equal('Something went horribly wrong!');
+	});
+
 	it('500 page returned when there is an error', async () => {
 		const app = await fixture.loadTestAdapterApp();
 		const request = new Request('http://example.com/causes-error');
diff --git a/packages/astro/test/test-adapter.js b/packages/astro/test/test-adapter.js
index 297e117a2..2bfc0bff4 100644
--- a/packages/astro/test/test-adapter.js
+++ b/packages/astro/test/test-adapter.js
@@ -27,9 +27,9 @@ export default function ({ provideAddress } = { provideAddress: true }) {
 											import { App } from 'astro/app';
 
 											class MyApp extends App {
-												render(request) {
+												render(request, routeData) {
 													${provideAddress ? `request[Symbol.for('astro.clientAddress')] = '0.0.0.0';` : ''}
-													return super.render(request);
+													return super.render(request, routeData);
 												}
 											}