[@astrojs/image] fixes a bug in dev when <Image /> is used with no transformation props (#4933)

* fix: return the original file in dev if no image transforms were used

* chore: add changeset

.changeset/khaki-ghosts-fry.md

@@ -0,0 +1,5 @@
+---
+'@astrojs/image': patch
+---
+
+Fixes a bug in dev when `<Image />` is used for a local image with no transformations

packages/integrations/image/src/vite-plugin-astro-image.ts

@@ -93,16 +93,20 @@ export function createPlugin(config: AstroConfig, options: Required<IntegrationO
 						url.searchParams
 					);
 
-					if (!transform) {
+					// if no transforms were added, the original file will be returned as-is
-						return next();
+					let data = file;
+					let format = meta.format;
+
+					if (transform) {
+						const result = await globalThis.astroImage.defaultLoader.transform(file, transform);
+						data = result.data;
+						format = result.format;
 					}
 
-					const result = await globalThis.astroImage.defaultLoader.transform(file, transform);
+					res.setHeader('Content-Type', `image/${format}`);
-
-					res.setHeader('Content-Type', `image/${result.format}`);
 					res.setHeader('Cache-Control', 'max-age=360000');
 
-					const stream = Readable.from(result.data);
+					const stream = Readable.from(data);
 					return stream.pipe(res);
 				}
 

packages/integrations/image/test/fixtures/basic-image/src/pages/index.astro

@@ -15,6 +15,8 @@ import { Image } from '@astrojs/image/components';
 		<br />
 		<Image id="social-jpg" src={socialJpg} width={506} height={253} alt="social-jpg" />
 		<br />
+		<Image id="no-transforms" src={socialJpg} alt="no-transforms" />
+		<br />
 		<Image id="google" src="https://www.google.com/images/branding/googlelogo/2x/googlelogo_color_272x92dp.png" width={544} height={184} format="webp" alt="Google" />
 		<br />
 		<Image id="inline" src={import('../assets/social.jpg')} width={506} alt="inline" />

packages/integrations/image/test/image-ssg.test.js

@@ -28,6 +28,12 @@ describe('SSG images - dev', function () {
 			url: '/@astroimage/assets/social.jpg',
 			query: { f: 'jpg', w: '506', h: '253' },
 		},
+		{
+			title: 'Local image no transforms',
+			id: '#no-transforms',
+			url: '/@astroimage/assets/social.jpg',
+			query: { }
+		},
 		{
 			title: 'Filename with spaces',
 			id: '#spaces',

packages/integrations/image/test/image-ssr-dev.test.js

@@ -32,6 +32,13 @@ describe('SSR images - dev', function () {
 			query: { f: 'jpg', w: '506', h: '253' },
 			contentType: 'image/jpeg',
 		},
+		{
+			title: 'Local image no transforms',
+			id: '#no-transforms',
+			url: '/@astroimage/assets/social.jpg',
+			query: { },
+			contentType: 'image/jpeg',
+		},
 		{
 			title: 'Filename with spaces',
 			id: '#spaces',