fix: generate types even without src/content (#12565)

* fix: generate types even without src/content

* chore: add test

3 files changed, 30 insertions, 7 deletions

diff --git a/.changeset/blue-gorillas-accept.md b/.changeset/blue-gorillas-accept.md
new file mode 100644
index 000000000..b122a9558
--- /dev/null
+++ b/.changeset/blue-gorillas-accept.md
@@ -0,0 +1,5 @@
+---
+'astro': patch
+---
+
+Fixes a bug where content types were not generated when first running astro dev unless src/content exists
diff --git a/packages/astro/src/core/sync/index.ts b/packages/astro/src/core/sync/index.ts
index 67fdccc54..823470e97 100644
--- a/packages/astro/src/core/sync/index.ts
+++ b/packages/astro/src/core/sync/index.ts
@@ -86,7 +86,11 @@ export async function clearContentLayerCache({
 	settings,
 	logger,
 	fs = fsMod,
-}: { settings: AstroSettings; logger: Logger; fs?: typeof fsMod }) {
+}: {
+	settings: AstroSettings;
+	logger: Logger;
+	fs?: typeof fsMod;
+}) {
 	const dataStore = getDataStoreFile(settings);
 	if (fs.existsSync(dataStore)) {
 		logger.debug('content', 'clearing data store');
@@ -138,14 +142,21 @@ export async function syncInternal({
 		});
 		await contentLayer.sync();
 		settings.timer.end('Sync content layer');
-	} else if (fs.existsSync(fileURLToPath(getContentPaths(settings.config, fs).contentDir))) {
+	} else {
+		const paths = getContentPaths(settings.config, fs);
 		// Content is synced after writeFiles. That means references are not created
 		// To work around it, we create a stub so the reference is created and content
 		// sync will override the empty file
-		settings.injectedTypes.push({
-			filename: CONTENT_TYPES_FILE,
-			content: '',
-		});
+		if (
+			paths.config.exists ||
+			// Legacy collections don't require a config file
+			(settings.config.legacy?.collections && fs.existsSync(paths.contentDir))
+		) {
+			settings.injectedTypes.push({
+				filename: CONTENT_TYPES_FILE,
+				content: '',
+			});
+		}
 	}
 	syncAstroEnv(settings);
 
diff --git a/packages/astro/test/content-layer.test.js b/packages/astro/test/content-layer.test.js
index 16aa96c29..aaf7c594f 100644
--- a/packages/astro/test/content-layer.test.js
+++ b/packages/astro/test/content-layer.test.js
@@ -1,5 +1,5 @@
 import assert from 'node:assert/strict';
-import { promises as fs } from 'node:fs';
+import { promises as fs, existsSync } from 'node:fs';
 import { sep } from 'node:path';
 import { sep as posixSep } from 'node:path/posix';
 import { after, before, describe, it } from 'node:test';
@@ -313,6 +313,13 @@ describe('Content Layer', () => {
 			devServer?.stop();
 		});
 
+
+		it('Generates content types files', async () => {
+			assert.ok(existsSync(new URL('./.astro/content.d.ts', fixture.config.root)));
+			const data = await fs.readFile(new URL('./.astro/types.d.ts', fixture.config.root), 'utf-8');
+			assert.match(data, /<reference path="content.d.ts"/);
+		});
+
 		it('Returns custom loader collection', async () => {
 			assert.ok(json.hasOwnProperty('customLoader'));
 			assert.ok(Array.isArray(json.customLoader));