Fix build errors being ignored when using concurrency

.changeset/wide-adults-smell.md

@@ -0,0 +1,5 @@
+---
+'astro': patch
+---
+
+Fix build errors being ignored when build.concurrency > 1

packages/astro/src/core/build/generate.ts

@@ -297,7 +297,7 @@ async function generatePage(
 				const path = paths[i];
 				promises.push(limit(() => generatePathWithLogs(path, route, i, paths, true)));
 			}
-			await Promise.allSettled(promises);
+			await Promise.all(promises);
 		} else {
 			for (let i = 0; i < paths.length; i++) {
 				const path = paths[i];

packages/astro/test/build-concurrency.test.js

@@ -0,0 +1,29 @@
+import * as assert from 'node:assert/strict';
+import { before, describe, it } from 'node:test';
+import { loadFixture } from './test-utils.js';
+
+describe('Building with concurrency > 1', () => {
+	/** @type {import('./test-utils').Fixture} */
+	let fixture;
+
+	before(async () => {
+		fixture = await loadFixture({
+			root: './fixtures/build-concurrency/',
+			build: {
+				concurrency: 2,
+			},
+		});
+	});
+
+	it('Errors and exits', async () => {
+		let built = false
+		try {
+			await fixture.build();
+			built = true
+		} catch (err) {
+			assert.match(err.message, /This is a test/)
+		}
+
+		assert.equal(built, false, 'Build should not complete');
+	});
+});

packages/astro/test/fixtures/build-concurrency/package.json

@@ -0,0 +1,8 @@
+{
+  "name": "@test/concurrency",
+  "version": "0.0.0",
+  "private": true,
+  "dependencies": {
+    "astro": "workspace:*"
+  }
+}

packages/astro/test/fixtures/build-concurrency/src/pages/index.astro

@@ -0,0 +1,5 @@
+---
+throw Error('This is a test')
+---
+
+<h1>Hello world!</h1>

packages/astro/test/fixtures/build-concurrency/src/pages/page2.astro

@@ -0,0 +1,4 @@
+---
+---
+
+<h1>Page 2</h1>