Ensure base configuration appended to content collection styles (#6182)

* Fix, base appended to propagated scripts

* Test scripts

10 files changed, 108 insertions, 2 deletions

diff --git a/.changeset/late-poets-own.md b/.changeset/late-poets-own.md
new file mode 100644
index 000000000..1055bc71a
--- /dev/null
+++ b/.changeset/late-poets-own.md
@@ -0,0 +1,5 @@
+---
+'astro': patch
+---
+
+Ensure base configuration appended to content collection styles
diff --git a/packages/astro/src/content/vite-plugin-content-assets.ts b/packages/astro/src/content/vite-plugin-content-assets.ts
index 74378f4e0..c09162177 100644
--- a/packages/astro/src/content/vite-plugin-content-assets.ts
+++ b/packages/astro/src/content/vite-plugin-content-assets.ts
@@ -98,6 +98,7 @@ export function astroConfigBuildPlugin(
 			},
 			'build:post': ({ ssrOutputs, clientOutputs, mutate }) => {
 				const outputs = ssrOutputs.flatMap((o) => o.output);
+				const prependBase = (src: string) => prependForwardSlash(npath.posix.join(options.settings.config.base, src));
 				for (const chunk of outputs) {
 					if (
 						chunk.type === 'chunk' &&
@@ -133,7 +134,7 @@ export function astroConfigBuildPlugin(
 						if (entryCSS.size) {
 							newCode = newCode.replace(
 								JSON.stringify(LINKS_PLACEHOLDER),
-								JSON.stringify([...entryCSS])
+								JSON.stringify(Array.from(entryCSS).map(prependBase))
 							);
 						}
 						if (entryScripts.size) {
@@ -153,7 +154,7 @@ export function astroConfigBuildPlugin(
 								JSON.stringify(
 									[...entryFileNames].map((src) => ({
 										props: {
-											src: prependForwardSlash(npath.posix.join(options.settings.config.base, src)),
+											src: prependBase(src),
 											type: 'module',
 										},
 										children: '',
diff --git a/packages/astro/test/content-collections.test.js b/packages/astro/test/content-collections.test.js
index c8105184e..148fa01ca 100644
--- a/packages/astro/test/content-collections.test.js
+++ b/packages/astro/test/content-collections.test.js
@@ -243,4 +243,27 @@ describe('Content Collections', () => {
 			}
 		});
 	});
+
+	describe('Base configuration', () => {
+		let fixture;
+
+		before(async () => {
+			fixture = await loadFixture({
+				root: './fixtures/content-collections-base/',
+			});
+			await fixture.build();
+		});
+
+		it('Includes base in links', async () => {
+			const html = await fixture.readFile('/docs/index.html');
+			const $ = cheerio.load(html);
+			expect($('link').attr('href')).to.satisfies(a => a.startsWith('/docs'))
+		});
+
+		it('Includes base in hoisted scripts', async () => {
+			const html = await fixture.readFile('/docs/index.html');
+			const $ = cheerio.load(html);
+			expect($('script').attr('src')).to.satisfies(a => a.startsWith('/docs'))
+		});
+	});
 });
diff --git a/packages/astro/test/fixtures/content-collections-base/astro.config.mjs b/packages/astro/test/fixtures/content-collections-base/astro.config.mjs
new file mode 100644
index 000000000..b11c49cea
--- /dev/null
+++ b/packages/astro/test/fixtures/content-collections-base/astro.config.mjs
@@ -0,0 +1,13 @@
+import { defineConfig } from 'astro/config';
+import mdx from '@astrojs/mdx';
+
+// https://astro.build/config
+export default defineConfig({
+	base: '/docs',
+	integrations: [mdx()],
+	vite: {
+		build: {
+			assetsInlineLimit: 0
+		}
+	}
+});
diff --git a/packages/astro/test/fixtures/content-collections-base/package.json b/packages/astro/test/fixtures/content-collections-base/package.json
new file mode 100644
index 000000000..152a02919
--- /dev/null
+++ b/packages/astro/test/fixtures/content-collections-base/package.json
@@ -0,0 +1,9 @@
+{
+  "name": "@test/content-collections-base",
+  "version": "0.0.0",
+  "private": true,
+  "dependencies": {
+    "astro": "workspace:*",
+    "@astrojs/mdx": "workspace:*"
+  }
+}
diff --git a/packages/astro/test/fixtures/content-collections-base/src/components/One.astro b/packages/astro/test/fixtures/content-collections-base/src/components/One.astro
new file mode 100644
index 000000000..69dda4a61
--- /dev/null
+++ b/packages/astro/test/fixtures/content-collections-base/src/components/One.astro
@@ -0,0 +1,7 @@
+<style>
+	div { color: blue; }
+</style>
+<script>
+	console.log('hi');
+</script>
+<div>Testing</div>
diff --git a/packages/astro/test/fixtures/content-collections-base/src/content/config.ts b/packages/astro/test/fixtures/content-collections-base/src/content/config.ts
new file mode 100644
index 000000000..439a3533a
--- /dev/null
+++ b/packages/astro/test/fixtures/content-collections-base/src/content/config.ts
@@ -0,0 +1,12 @@
+import { z, defineCollection } from 'astro:content';
+
+
+const docs = defineCollection({
+	schema: z.object({
+		title: z.string(),
+	}),
+});
+
+export const collections = {
+	docs,
+}
diff --git a/packages/astro/test/fixtures/content-collections-base/src/content/docs/one.mdx b/packages/astro/test/fixtures/content-collections-base/src/content/docs/one.mdx
new file mode 100644
index 000000000..223b22a40
--- /dev/null
+++ b/packages/astro/test/fixtures/content-collections-base/src/content/docs/one.mdx
@@ -0,0 +1,11 @@
+---
+title: One
+---
+
+import One from '../../components/One.astro';
+
+# Title
+
+stuff
+
+<One />
diff --git a/packages/astro/test/fixtures/content-collections-base/src/pages/docs.astro b/packages/astro/test/fixtures/content-collections-base/src/pages/docs.astro
new file mode 100644
index 000000000..6b352ce37
--- /dev/null
+++ b/packages/astro/test/fixtures/content-collections-base/src/pages/docs.astro
@@ -0,0 +1,17 @@
+---
+import { getEntryBySlug } from 'astro:content';
+const entry = await getEntryBySlug('docs', 'one');
+const { Content } = await entry.render();
+---
+<html lang="en">
+  <head>
+    <meta charset="utf-8" />
+    <meta name="viewport" content="width=device-width" />
+    <title>It's content time!</title>
+  </head>
+  <body>
+    <main>
+			<Content />
+    </main>
+  </body>
+</html>
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index a296a150d..3e1a40bf7 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -1663,6 +1663,14 @@ importers:
       '@astrojs/mdx': link:../../../../integrations/mdx
       astro: link:../../..
 
+  packages/astro/test/fixtures/content-collections-base:
+    specifiers:
+      '@astrojs/mdx': workspace:*
+      astro: workspace:*
+    dependencies:
+      '@astrojs/mdx': link:../../../../integrations/mdx
+      astro: link:../../..
+
   packages/astro/test/fixtures/content-ssr-integration:
     specifiers:
       '@astrojs/mdx': workspace:*