From 46055a63e6874753e21701edc6c45c812a81c67c Mon Sep 17 00:00:00 2001
From: Matt Kane <m@mk.gg>
Date: Tue, 12 Nov 2024 16:26:50 +0000
Subject: [PATCH] feat: add crop support to image services (#12414)

* wip: add crop support to image services

* Add tests

* Strip crop attributes

* Don't upscale

* Format

* Get build working properly

* Changes from review
---
 packages/astro/components/Image.astro         |  38 ++--
 packages/astro/src/assets/consts.ts           |  10 +-
 packages/astro/src/assets/internal.ts         |  12 +-
 packages/astro/src/assets/layout.ts           |   6 +-
 packages/astro/src/assets/services/service.ts |  23 +-
 packages/astro/src/assets/services/sharp.ts   |  42 +++-
 packages/astro/src/assets/types.ts            |   7 +-
 packages/astro/src/types/public/config.ts     |   5 +-
 packages/astro/test/core-image-layout.test.js |  60 ++++-
 .../astro/test/core-image-service.test.js     | 206 ++++++++++++++++++
 .../core-image-layout/src/pages/build.astro   |  66 ++++++
 .../core-image-layout/src/pages/fit.astro     |  35 +++
 12 files changed, 466 insertions(+), 44 deletions(-)
 create mode 100644 packages/astro/test/core-image-service.test.js
 create mode 100644 packages/astro/test/fixtures/core-image-layout/src/pages/build.astro
 create mode 100644 packages/astro/test/fixtures/core-image-layout/src/pages/fit.astro

diff --git a/packages/astro/components/Image.astro b/packages/astro/components/Image.astro
index b873e1ebad..70cbc0f456 100644
--- a/packages/astro/components/Image.astro
+++ b/packages/astro/components/Image.astro
@@ -23,6 +23,20 @@ if (typeof props.height === 'string') {
 	props.height = parseInt(props.height);
 }
 
+const { experimentalResponsiveImages } = imageConfig;
+
+const layoutClassMap = {
+	fixed: 'aim-fi',
+	responsive: 'aim-re',
+};
+
+if (experimentalResponsiveImages) {
+	// Apply defaults from imageConfig if not provided
+	props.layout ??= imageConfig.experimentalLayout;
+	props.fit ??= imageConfig.experimentalObjectFit ?? 'cover';
+	props.position ??= imageConfig.experimentalObjectPosition ?? 'center';
+}
+
 const image = await getImage(props);
 
 const additionalAttributes: HTMLAttributes<'img'> = {};
@@ -34,16 +48,7 @@ if (import.meta.env.DEV) {
 	additionalAttributes['data-image-component'] = 'true';
 }
 
-const { experimentalResponsiveImages } = imageConfig;
-
-const layoutClassMap = {
-	fixed: 'aim-fi',
-	responsive: 'aim-re',
-};
-
 const cssFitValues = ['fill', 'contain', 'cover', 'scale-down'];
-const objectFit = props.fit ?? imageConfig.experimentalObjectFit ?? 'cover';
-const objectPosition = props.position ?? imageConfig.experimentalObjectPosition ?? 'center';
 
 // The style prop can't be spread when using define:vars, so we need to extract it here
 // @see https://github.com/withastro/compiler/issues/1050
@@ -51,7 +56,7 @@ const { style = '', class: className, ...attrs } = { ...additionalAttributes, ..
 ---
 
 {
-	experimentalResponsiveImages ? (
+	experimentalResponsiveImages && props.layout ? (
 		<img
 			src={image.src}
 			{...attrs}
@@ -64,12 +69,13 @@ const { style = '', class: className, ...attrs } = { ...additionalAttributes, ..
 }
 
 <style
-	define:vars={experimentalResponsiveImages && {
-		w: image.attributes.width ?? props.width ?? image.options.width,
-		h: image.attributes.height ?? props.height ?? image.options.height,
-		fit: cssFitValues.includes(objectFit) && objectFit,
-		pos: objectPosition,
-	}}
+	define:vars={experimentalResponsiveImages &&
+		props.layout && {
+			w: image.attributes.width ?? props.width ?? image.options.width,
+			h: image.attributes.height ?? props.height ?? image.options.height,
+			fit: cssFitValues.includes(props.fit) && props.fit,
+			pos: props.position,
+		}}
 >
 	/* Shared by all Astro images */
 	.aim {
diff --git a/packages/astro/src/assets/consts.ts b/packages/astro/src/assets/consts.ts
index 15f9fe46fb..5fae641ae4 100644
--- a/packages/astro/src/assets/consts.ts
+++ b/packages/astro/src/assets/consts.ts
@@ -26,4 +26,12 @@ export const VALID_SUPPORTED_FORMATS = [
 ] as const;
 export const DEFAULT_OUTPUT_FORMAT = 'webp' as const;
 export const VALID_OUTPUT_FORMATS = ['avif', 'png', 'webp', 'jpeg', 'jpg', 'svg'] as const;
-export const DEFAULT_HASH_PROPS = ['src', 'width', 'height', 'format', 'quality'];
+export const DEFAULT_HASH_PROPS = [
+	'src',
+	'width',
+	'height',
+	'format',
+	'quality',
+	'fit',
+	'position',
+];
diff --git a/packages/astro/src/assets/internal.ts b/packages/astro/src/assets/internal.ts
index 235f1115be..fb1733dcf7 100644
--- a/packages/astro/src/assets/internal.ts
+++ b/packages/astro/src/assets/internal.ts
@@ -2,6 +2,12 @@ import { isRemotePath } from '@astrojs/internal-helpers/path';
 import { AstroError, AstroErrorData } from '../core/errors/index.js';
 import type { AstroConfig } from '../types/public/config.js';
 import { DEFAULT_HASH_PROPS } from './consts.js';
+import {
+	DEFAULT_RESOLUTIONS,
+	LIMITED_RESOLUTIONS,
+	getSizesAttribute,
+	getWidths,
+} from './layout.js';
 import { type ImageService, isLocalService } from './services/service.js';
 import {
 	type GetImageResult,
@@ -12,12 +18,6 @@ import {
 } from './types.js';
 import { isESMImportedImage, isRemoteImage, resolveSrc } from './utils/imageKind.js';
 import { inferRemoteSize } from './utils/remoteProbe.js';
-import {
-	DEFAULT_RESOLUTIONS,
-	getSizesAttribute,
-	getWidths,
-	LIMITED_RESOLUTIONS,
-} from './layout.js';
 
 export async function getConfiguredImageService(): Promise<ImageService> {
 	if (!globalThis?.astroAsset?.imageService) {
diff --git a/packages/astro/src/assets/layout.ts b/packages/astro/src/assets/layout.ts
index a7fabf4e13..adc117f399 100644
--- a/packages/astro/src/assets/layout.ts
+++ b/packages/astro/src/assets/layout.ts
@@ -1,4 +1,4 @@
-import type { ImageLayout } from '../types/public/index.js';
+import type { ImageLayout } from './types.js';
 
 // Common screen widths. These will be filtered according to the image size and layout
 export const DEFAULT_RESOLUTIONS = [
@@ -33,9 +33,9 @@ export const LIMITED_RESOLUTIONS = [
 
 /**
  * Gets the breakpoints for an image, based on the layout and width
- * 
+ *
  * The rules are as follows:
- * 
+ *
  * - For full-width layout we return all breakpoints smaller than the original image width
  * - For fixed layout we return 1x and 2x the requested width, unless the original image is smaller than that.
  * - For responsive layout we return all breakpoints smaller than 2x the requested width, unless the original image is smaller than that.
diff --git a/packages/astro/src/assets/services/service.ts b/packages/astro/src/assets/services/service.ts
index 23c983b8c5..d84ec1728e 100644
--- a/packages/astro/src/assets/services/service.ts
+++ b/packages/astro/src/assets/services/service.ts
@@ -2,7 +2,12 @@ import { AstroError, AstroErrorData } from '../../core/errors/index.js';
 import { isRemotePath, joinPaths } from '../../core/path.js';
 import type { AstroConfig } from '../../types/public/config.js';
 import { DEFAULT_HASH_PROPS, DEFAULT_OUTPUT_FORMAT, VALID_SUPPORTED_FORMATS } from '../consts.js';
-import type { ImageOutputFormat, ImageTransform, UnresolvedSrcSetValue } from '../types.js';
+import type {
+	ImageFit,
+	ImageOutputFormat,
+	ImageTransform,
+	UnresolvedSrcSetValue,
+} from '../types.js';
 import { isESMImportedImage } from '../utils/imageKind.js';
 import { isRemoteAllowed } from '../utils/remotePattern.js';
 
@@ -116,6 +121,8 @@ export type BaseServiceTransform = {
 	height?: number;
 	format: string;
 	quality?: string | null;
+	fit?: ImageFit;
+	position?: string;
 };
 
 const sortNumeric = (a: number, b: number) => a - b;
@@ -221,7 +228,13 @@ export const baseService: Omit<LocalImageService, 'transform'> = {
 		// Sometimes users will pass number generated from division, which can result in floating point numbers
 		if (options.width) options.width = Math.round(options.width);
 		if (options.height) options.height = Math.round(options.height);
-
+		if (options.layout && options.width && options.height) {
+			options.fit ??= 'cover';
+			delete options.layout;
+		}
+		if (options.fit === 'none') {
+			delete options.fit;
+		}
 		return options;
 	},
 	getHTMLAttributes(options) {
@@ -237,6 +250,8 @@ export const baseService: Omit<LocalImageService, 'transform'> = {
 			formats,
 			layout,
 			priority,
+			fit,
+			position,
 			...attributes
 		} = options;
 		return {
@@ -344,6 +359,8 @@ export const baseService: Omit<LocalImageService, 'transform'> = {
 			h: 'height',
 			q: 'quality',
 			f: 'format',
+			fit: 'fit',
+			position: 'position',
 		};
 
 		Object.entries(params).forEach(([param, key]) => {
@@ -366,6 +383,8 @@ export const baseService: Omit<LocalImageService, 'transform'> = {
 			height: params.has('h') ? parseInt(params.get('h')!) : undefined,
 			format: params.get('f') as ImageOutputFormat,
 			quality: params.get('q'),
+			fit: params.get('fit') as ImageFit,
+			position: params.get('position') ?? undefined,
 		};
 
 		return transform;
diff --git a/packages/astro/src/assets/services/sharp.ts b/packages/astro/src/assets/services/sharp.ts
index c9df4c269a..bbae39eb09 100644
--- a/packages/astro/src/assets/services/sharp.ts
+++ b/packages/astro/src/assets/services/sharp.ts
@@ -1,6 +1,6 @@
-import type { FormatEnum, SharpOptions } from 'sharp';
+import type { FitEnum, FormatEnum, SharpOptions } from 'sharp';
 import { AstroError, AstroErrorData } from '../../core/errors/index.js';
-import type { ImageOutputFormat, ImageQualityPreset } from '../types.js';
+import type { ImageFit, ImageOutputFormat, ImageQualityPreset } from '../types.js';
 import {
 	type BaseServiceTransform,
 	type LocalImageService,
@@ -38,6 +38,16 @@ async function loadSharp() {
 	return sharpImport;
 }
 
+const fitMap: Record<ImageFit, keyof FitEnum> = {
+	fill: 'fill',
+	contain: 'inside',
+	cover: 'cover',
+	none: 'outside',
+	'scale-down': 'inside',
+	outside: 'outside',
+	inside: 'inside',
+};
+
 const sharpService: LocalImageService<SharpImageServiceConfig> = {
 	validateOptions: baseService.validateOptions,
 	getURL: baseService.getURL,
@@ -46,7 +56,6 @@ const sharpService: LocalImageService<SharpImageServiceConfig> = {
 	getSrcSet: baseService.getSrcSet,
 	async transform(inputBuffer, transformOptions, config) {
 		if (!sharp) sharp = await loadSharp();
-
 		const transform: BaseServiceTransform = transformOptions as BaseServiceTransform;
 
 		// Return SVGs as-is
@@ -62,11 +71,30 @@ const sharpService: LocalImageService<SharpImageServiceConfig> = {
 		// always call rotate to adjust for EXIF data orientation
 		result.rotate();
 
-		// Never resize using both width and height at the same time, prioritizing width.
-		if (transform.height && !transform.width) {
-			result.resize({ height: Math.round(transform.height) });
+		// If `fit` isn't set then use old behavior:
+		// - Do not use both width and height for resizing, and prioritize width over height
+		// - Allow enlarging images
+
+		const withoutEnlargement = Boolean(transform.fit);
+		if (transform.width && transform.height && transform.fit) {
+			const fit: keyof FitEnum = fitMap[transform.fit] ?? 'inside';
+			result.resize({
+				width: Math.round(transform.width),
+				height: Math.round(transform.height),
+				fit,
+				position: transform.position,
+				withoutEnlargement,
+			});
+		} else if (transform.height && !transform.width) {
+			result.resize({
+				height: Math.round(transform.height),
+				withoutEnlargement,
+			});
 		} else if (transform.width) {
-			result.resize({ width: Math.round(transform.width) });
+			result.resize({
+				width: Math.round(transform.width),
+				withoutEnlargement,
+			});
 		}
 
 		if (transform.format) {
diff --git a/packages/astro/src/assets/types.ts b/packages/astro/src/assets/types.ts
index e4687adfdf..0e46cfb451 100644
--- a/packages/astro/src/assets/types.ts
+++ b/packages/astro/src/assets/types.ts
@@ -1,4 +1,3 @@
-import type { ImageLayout } from '../types/public/index.js';
 import type { OmitPreservingIndexSignature, Simplify, WithRequired } from '../type-utils.js';
 import type { VALID_INPUT_FORMATS, VALID_OUTPUT_FORMATS } from './consts.js';
 import type { ImageService } from './services/service.js';
@@ -7,6 +6,8 @@ export type ImageQualityPreset = 'low' | 'mid' | 'high' | 'max' | (string & {});
 export type ImageQuality = ImageQualityPreset | number;
 export type ImageInputFormat = (typeof VALID_INPUT_FORMATS)[number];
 export type ImageOutputFormat = (typeof VALID_OUTPUT_FORMATS)[number] | (string & {});
+export type ImageLayout = 'responsive' | 'fixed' | 'full-width' | 'none';
+export type ImageFit = 'fill' | 'contain' | 'cover' | 'none' | 'scale-down' | (string & {});
 
 export type AssetsGlobalStaticImagesList = Map<
 	string,
@@ -87,6 +88,8 @@ export type ImageTransform = {
 	height?: number | undefined;
 	quality?: ImageQuality | undefined;
 	format?: ImageOutputFormat | undefined;
+	fit?: ImageFit | undefined;
+	position?: string | undefined;
 	[key: string]: any;
 };
 
@@ -157,7 +160,7 @@ type ImageSharedProps<T> = T & {
 
 	layout?: ImageLayout;
 
-	fit?: 'fill' | 'contain' | 'cover' | 'none' | 'scale-down' | (string & {});
+	fit?: ImageFit;
 
 	position?: string;
 } & (
diff --git a/packages/astro/src/types/public/config.ts b/packages/astro/src/types/public/config.ts
index ce4052b437..fd1617d897 100644
--- a/packages/astro/src/types/public/config.ts
+++ b/packages/astro/src/types/public/config.ts
@@ -6,6 +6,7 @@ import type {
 	ShikiConfig,
 } from '@astrojs/markdown-remark';
 import type { UserConfig as OriginalViteUserConfig, SSROptions as ViteSSROptions } from 'vite';
+import type { ImageFit, ImageLayout } from '../../assets/types.js';
 import type { RemotePattern } from '../../assets/utils/remotePattern.js';
 import type { AssetsPrefix } from '../../core/app/types.js';
 import type { AstroConfigType } from '../../core/config/schema.js';
@@ -1091,7 +1092,7 @@ export interface ViteUserConfig extends OriginalViteUserConfig {
 		 * The default object-fit value for responsive images. Can be overridden by the `fit` prop on the image component.
 		 * Requires the `experimental.responsiveImages` flag to be enabled.
 		 */
-		experimentalObjectFit?: 'contain' | 'cover' | 'fill' | 'none' | 'scale-down' | (string & {});
+		experimentalObjectFit?: ImageFit;
 		/**
 		 * @docs
 		 * @name image.experimentalObjectPosition
@@ -1766,8 +1767,6 @@ export interface ViteUserConfig extends OriginalViteUserConfig {
 	};
 }
 
-export type ImageLayout = 'responsive' | 'fixed' | 'full-width' | 'none';
-
 /**
  * Resolved Astro Config
  *
diff --git a/packages/astro/test/core-image-layout.test.js b/packages/astro/test/core-image-layout.test.js
index 205336c0c7..e2f1c954e8 100644
--- a/packages/astro/test/core-image-layout.test.js
+++ b/packages/astro/test/core-image-layout.test.js
@@ -5,8 +5,8 @@ import * as cheerio from 'cheerio';
 import parseSrcset from 'parse-srcset';
 import { Logger } from '../dist/core/logger/core.js';
 import { testImageService } from './test-image-service.js';
-import { loadFixture } from './test-utils.js';
 import { testRemoteImageService } from './test-remote-image-service.js';
+import { loadFixture } from './test-utils.js';
 
 describe('astro:image:layout', () => {
 	/** @type {import('./test-utils').Fixture} */
@@ -15,8 +15,6 @@ describe('astro:image:layout', () => {
 	describe('local image service', () => {
 		/** @type {import('./test-utils').DevServer} */
 		let devServer;
-		/** @type {Array<{ type: any, level: 'error', message: string; }>} */
-		let logs = [];
 
 		before(async () => {
 			fixture = await loadFixture({
@@ -134,7 +132,7 @@ describe('astro:image:layout', () => {
 				assert.match(style, /\.aim\[/);
 				assert.match(style, /\.aim-re\[/);
 				assert.match(style, /\.aim-fi\[/);
-			})
+			});
 		});
 
 		describe('srcsets', () => {
@@ -180,6 +178,60 @@ describe('astro:image:layout', () => {
 			});
 		});
 
+		describe('generated URLs', () => {
+			let $;
+			before(async () => {
+				let res = await fixture.fetch('/fit');
+				let html = await res.text();
+				$ = cheerio.load(html);
+			});
+			it('generates width and height in image URLs when both are provided', () => {
+				let $img = $('#local-both img');
+				const aspectRatio = 300 / 400;
+				const srcset = parseSrcset($img.attr('srcset'));
+				for (const { url } of srcset) {
+					const params = new URL(url, 'https://example.com').searchParams;
+					const width = parseInt(params.get('w'));
+					const height = parseInt(params.get('h'));
+					assert.equal(width / height, aspectRatio);
+				}
+			});
+
+			it('does not pass through fit and position', async () => {
+				const fit = $('#fit-cover img');
+				assert.ok(!fit.attr('fit'));
+				const position = $('#position img');
+				assert.ok(!position.attr('position'));
+			});
+
+			it('sets a default fit of "cover" when no fit is provided', () => {
+				let $img = $('#fit-default img');
+				const srcset = parseSrcset($img.attr('srcset'));
+				for (const { url } of srcset) {
+					const params = new URL(url, 'https://example.com').searchParams;
+					assert.equal(params.get('fit'), 'cover');
+				}
+			});
+
+			it('sets a fit of "contain" when fit="contain" is provided', () => {
+				let $img = $('#fit-contain img');
+				const srcset = parseSrcset($img.attr('srcset'));
+				for (const { url } of srcset) {
+					const params = new URL(url, 'https://example.com').searchParams;
+					assert.equal(params.get('fit'), 'contain');
+				}
+			});
+
+			it('sets no fit when fit="none" is provided', () => {
+				let $img = $('#fit-none img');
+				const srcset = parseSrcset($img.attr('srcset'));
+				for (const { url } of srcset) {
+					const params = new URL(url, 'https://example.com').searchParams;
+					assert.ok(!params.has('fit'));
+				}
+			});
+		});
+
 		describe('remote images', () => {
 			describe('srcset', () => {
 				let $;
diff --git a/packages/astro/test/core-image-service.test.js b/packages/astro/test/core-image-service.test.js
new file mode 100644
index 0000000000..0c75ed484f
--- /dev/null
+++ b/packages/astro/test/core-image-service.test.js
@@ -0,0 +1,206 @@
+import assert from 'node:assert/strict';
+import { after, before, describe, it } from 'node:test';
+import { removeDir } from '@astrojs/internal-helpers/fs';
+import * as cheerio from 'cheerio';
+import { lookup as probe } from '../dist/assets/utils/vendor/image-size/lookup.js';
+import { loadFixture } from './test-utils.js';
+
+async function getImageDimensionsFromFixture(fixture, path) {
+	/** @type { Response } */
+	const res = await fixture.fetch(path instanceof URL ? path.pathname + path.search : path);
+	const buffer = await res.arrayBuffer();
+	const { width, height } = await probe(new Uint8Array(buffer));
+	return { width, height };
+}
+
+async function getImageDimensionsFromLocalFile(fixture, path) {
+	const buffer = await fixture.readFile(path, null);
+	const { width, height } = await probe(new Uint8Array(buffer));
+	return { width, height };
+}
+
+describe('astro image service', () => {
+	/** @type {import('./test-utils').Fixture} */
+	let fixture;
+
+	describe('dev image service', () => {
+		/** @type {import('./test-utils').DevServer} */
+		let devServer;
+
+		before(async () => {
+			fixture = await loadFixture({
+				root: './fixtures/core-image-layout/',
+				image: {
+					domains: ['unsplash.com'],
+				},
+			});
+
+			devServer = await fixture.startDevServer({});
+		});
+
+		after(async () => {
+			await devServer.stop();
+		});
+
+		describe('generated images', () => {
+			let $;
+			let src;
+			before(async () => {
+				const res = await fixture.fetch('/fit');
+				const html = await res.text();
+				$ = cheerio.load(html);
+				let $img = $('#local-both img');
+				src = new URL($img.attr('src'), 'http://localhost').href;
+			});
+
+			it('generates correct width and height when both are provided', async () => {
+				const url = new URL(src);
+				const { width, height } = await getImageDimensionsFromFixture(fixture, url);
+				assert.equal(width, 300);
+				assert.equal(height, 400);
+			});
+
+			it('generates correct height when only width is provided', async () => {
+				const url = new URL(src);
+				url.searchParams.delete('h');
+				const { width, height } = await getImageDimensionsFromFixture(fixture, url);
+				assert.equal(width, 300);
+				assert.equal(height, 200);
+			});
+
+			it('generates correct width when only height is provided', async () => {
+				const url = new URL(src);
+				url.searchParams.delete('w');
+				url.searchParams.set('h', '400');
+				const { width, height } = await getImageDimensionsFromFixture(fixture, url);
+				assert.equal(width, 600);
+				assert.equal(height, 400);
+			});
+
+			it('preserves aspect ratio when fit=inside', async () => {
+				const url = new URL(src);
+				url.searchParams.set('fit', 'inside');
+				const { width, height } = await getImageDimensionsFromFixture(fixture, url);
+				assert.equal(width, 300);
+				assert.equal(height, 200);
+			});
+
+			it('preserves aspect ratio when fit=contain', async () => {
+				const url = new URL(src);
+				url.searchParams.set('fit', 'contain');
+				const { width, height } = await getImageDimensionsFromFixture(fixture, url);
+				assert.equal(width, 300);
+				assert.equal(height, 200);
+			});
+
+			it('preserves aspect ratio when fit=outside', async () => {
+				const url = new URL(src);
+				url.searchParams.set('fit', 'outside');
+				const { width, height } = await getImageDimensionsFromFixture(fixture, url);
+				assert.equal(width, 600);
+				assert.equal(height, 400);
+			});
+			const originalWidth = 2316;
+			const originalHeight = 1544;
+			it('does not upscale image if requested size is larger than original', async () => {
+				const url = new URL(src);
+				url.searchParams.set('w', '3000');
+				url.searchParams.set('h', '2000');
+				const { width, height } = await getImageDimensionsFromFixture(fixture, url);
+				assert.equal(width, originalWidth);
+				assert.equal(height, originalHeight);
+			});
+
+			// To match old behavior, we should upscale if the requested size is larger than the original
+			it('does upscale image if requested size is larger than original and fit is unset', async () => {
+				const url = new URL(src);
+				url.searchParams.set('w', '3000');
+				url.searchParams.set('h', '2000');
+				url.searchParams.delete('fit');
+				const { width, height } = await getImageDimensionsFromFixture(fixture, url);
+				assert.equal(width, 3000);
+				assert.equal(height, 2000);
+			});
+
+			// To match old behavior, we should upscale if the requested size is larger than the original
+			it('does not upscale is only one dimension is provided and fit is set', async () => {
+				const url = new URL(src);
+				url.searchParams.set('w', '3000');
+				url.searchParams.delete('h');
+				url.searchParams.set('fit', 'cover');
+				const { width, height } = await getImageDimensionsFromFixture(fixture, url);
+				assert.equal(width, originalWidth);
+				assert.equal(height, originalHeight);
+			});
+		});
+	});
+
+	describe('build image service', () => {
+		before(async () => {
+			fixture = await loadFixture({
+				root: './fixtures/core-image-layout/',
+			});
+			removeDir(new URL('./fixtures/core-image-ssg/node_modules/.astro', import.meta.url));
+
+			await fixture.build();
+		});
+
+		describe('generated images', () => {
+			let $;
+			before(async () => {
+				const html = await fixture.readFile('/build/index.html');
+				$ = cheerio.load(html);
+			});
+
+			it('generates correct width and height when both are provided', async () => {
+				const path = $('.both img').attr('src');
+				const { width, height } = await getImageDimensionsFromLocalFile(fixture, path);
+				assert.equal(width, 300);
+				assert.equal(height, 400);
+			});
+
+			it('generates correct height when only width is provided', async () => {
+				const path = $('.width-only img').attr('src');
+				const { width, height } = await getImageDimensionsFromLocalFile(fixture, path);
+				assert.equal(width, 300);
+				assert.equal(height, 200);
+			});
+
+			it('generates correct width when only height is provided', async () => {
+				const path = $('.height-only img').attr('src');
+				const { width, height } = await getImageDimensionsFromLocalFile(fixture, path);
+				assert.equal(width, 600);
+				assert.equal(height, 400);
+			});
+
+			it('preserves aspect ratio when fit=inside', async () => {
+				const path = $('.fit-inside img').attr('src');
+				const { width, height } = await getImageDimensionsFromLocalFile(fixture, path);
+				assert.equal(width, 300);
+				assert.equal(height, 200);
+			});
+
+			it('preserves aspect ratio when fit=contain', async () => {
+				const path = $('.fit-contain img').attr('src');
+				const { width, height } = await getImageDimensionsFromLocalFile(fixture, path);
+				assert.equal(width, 300);
+				assert.equal(height, 200);
+			});
+
+			it('preserves aspect ratio when fit=outside', async () => {
+				const path = $('.fit-outside img').attr('src');
+				const { width, height } = await getImageDimensionsFromLocalFile(fixture, path);
+				assert.equal(width, 600);
+				assert.equal(height, 400);
+			});
+			const originalWidth = 2316;
+			const originalHeight = 1544;
+			it('does not upscale image if requested size is larger than original', async () => {
+				const path = $('.too-large img').attr('src');
+				const { width, height } = await getImageDimensionsFromLocalFile(fixture, path);
+				assert.equal(width, originalWidth);
+				assert.equal(height, originalHeight);
+			});
+		});
+	});
+});
diff --git a/packages/astro/test/fixtures/core-image-layout/src/pages/build.astro b/packages/astro/test/fixtures/core-image-layout/src/pages/build.astro
new file mode 100644
index 0000000000..a4a0cc9083
--- /dev/null
+++ b/packages/astro/test/fixtures/core-image-layout/src/pages/build.astro
@@ -0,0 +1,66 @@
+---
+import { Image } from "astro:assets";
+import penguin from "../assets/penguin.jpg";
+---
+
+<div class="both">
+	<Image src={penguin} alt="a penguin" width={300} height={400}/>
+</div>
+
+<div class="width-only">
+	<Image src={penguin} alt="a penguin" width={300}/>
+</div>
+
+<div class="height-only">
+	<Image src={penguin} alt="a penguin" height={400}/>
+</div>
+
+<div class="fit-contain">
+	<Image 
+		src={penguin} 
+		alt="a penguin" 
+		width={300} 
+		height={400} 
+		fit="contain"
+	/>
+</div>
+
+<div class="fit-scale-down">
+	<Image 
+		src={penguin} 
+		alt="a penguin" 
+		width={300} 
+		height={400} 
+		fit="scale-down"
+	/>
+</div>
+
+<div class="fit-outside">
+	<Image 
+		src={penguin} 
+		alt="a penguin" 
+		width={300} 
+		height={400} 
+		fit="outside"
+	/>
+</div>
+
+<div class="fit-inside">
+	<Image 
+		src={penguin} 
+		alt="a penguin" 
+		width={300} 
+		height={400} 
+		fit="inside"
+	/>
+</div>
+
+<div class="too-large">
+	<Image 
+		src={penguin} 
+		alt="a penguin" 
+		width={3000} 
+		height={2000} 
+		fit="cover"
+	/>
+</div>
diff --git a/packages/astro/test/fixtures/core-image-layout/src/pages/fit.astro b/packages/astro/test/fixtures/core-image-layout/src/pages/fit.astro
new file mode 100644
index 0000000000..442f4ffb0e
--- /dev/null
+++ b/packages/astro/test/fixtures/core-image-layout/src/pages/fit.astro
@@ -0,0 +1,35 @@
+---
+import { Image } from "astro:assets";
+import penguin from "../assets/penguin.jpg";
+---
+
+<div id="local-both">
+	<Image src={penguin} alt="a penguin" width={300} height={400}/>
+</div>
+<div id="fit-default">
+	<Image src={penguin} alt="a penguin" />
+</div>
+<div id="fit-fill">
+	<Image src={penguin} alt="a penguin" fit="fill" />
+</div>
+<div id="fit-contain">
+	<Image src={penguin} alt="a penguin" fit="contain" />
+</div>
+<div id="fit-cover">
+	<Image src={penguin} alt="a penguin" fit="cover" />
+</div>
+<div id="fit-scale-down">
+	<Image src={penguin} alt="a penguin" fit="scale-down" />
+</div>
+<div id="fit-inside">
+	<Image src={penguin} alt="a penguin" fit="inside" />
+</div>
+<div id="fit-none">
+	<Image src={penguin} alt="a penguin" fit="none" />
+</div>
+<div id="fit-unsupported">
+	<Image src={penguin} alt="a penguin" fit="unsupported" />
+</div>
+<div id="position">
+	<Image src={penguin} alt="a penguin" position="right top" />
+</div>