feat: set intrinsic width and height for SVGs (#13126)

Author: benmccann

.changeset/tricky-squids-provide.md

@@ -0,0 +1,5 @@
+---
+'@sveltejs/enhanced-img': patch
+---
+
+feat: set intrinsic width and height for SVGs

packages/enhanced-img/package.json

@@ -37,6 +37,7 @@
 	"types": "types/index.d.ts",
 	"dependencies": {
 		"magic-string": "^0.30.5",
+		"sharp": "^0.33.5",
 		"svelte-parse-markup": "^0.1.5",
 		"vite-imagetools": "^7.0.1",
 		"zimmerframe": "^1.1.2"

packages/enhanced-img/src/preprocessor.js

@@ -4,8 +4,9 @@ import { existsSync } from 'node:fs';
 import * as path from 'node:path';
 
 import MagicString from 'magic-string';
-import { walk } from 'zimmerframe';
+import sharp from 'sharp';
 import { parse } from 'svelte-parse-markup';
+import { walk } from 'zimmerframe';
 
 // TODO: expose this in vite-imagetools rather than duplicating it
 const OPTIMIZABLE = /^[^?]+\.(avif|heif|gif|jpeg|jpg|png|tiff|webp)(\?.*)?$/;
@@ -70,51 +71,51 @@ export function image(opts) {
 				const original_url = src_attribute.raw.trim();
 				let url = original_url;
 
-				const sizes = get_attr_value(node, 'sizes');
-				const width = get_attr_value(node, 'width');
-				url += url.includes('?') ? '&' : '?';
-				if (sizes && 'raw' in sizes) {
-					url += 'imgSizes=' + encodeURIComponent(sizes.raw) + '&';
-				}
-				if (width && 'raw' in width) {
-					url += 'imgWidth=' + encodeURIComponent(width.raw) + '&';
+				if (OPTIMIZABLE.test(url)) {
+					const sizes = get_attr_value(node, 'sizes');
+					const width = get_attr_value(node, 'width');
+					url += url.includes('?') ? '&' : '?';
+					if (sizes && 'raw' in sizes) {
+						url += 'imgSizes=' + encodeURIComponent(sizes.raw) + '&';
+					}
+					if (width && 'raw' in width) {
+						url += 'imgWidth=' + encodeURIComponent(width.raw) + '&';
+					}
+					url += 'enhanced';
 				}
-				url += 'enhanced';
 
-				if (OPTIMIZABLE.test(url)) {
-					// resolves the import so that we can build the entire picture template string and don't
-					// need any logic blocks
-					const resolved_id = (await opts.plugin_context.resolve(url, filename))?.id;
-					if (!resolved_id) {
-						const file_path = url.substring(0, url.indexOf('?'));
-						if (existsSync(path.resolve(opts.vite_config.publicDir, file_path))) {
-							throw new Error(
-								`Could not locate ${file_path}. Please move it to be located relative to the page in the routes directory or reference it beginning with /static/. See https://vitejs.dev/guide/assets for more details on referencing assets.`
-							);
-						}
+				// resolves the import so that we can build the entire picture template string and don't
+				// need any logic blocks
+				const resolved_id = (await opts.plugin_context.resolve(url, filename))?.id;
+				if (!resolved_id) {
+					const query_index = url.indexOf('?');
+					const file_path = query_index >= 0 ? url.substring(0, query_index) : url;
+					if (existsSync(path.resolve(opts.vite_config.publicDir, file_path))) {
 						throw new Error(
-							`Could not locate ${file_path}. See https://vitejs.dev/guide/assets for more details on referencing assets.`
+							`Could not locate ${file_path}. Please move it to be located relative to the page in the routes directory or reference it beginning with /static/. See https://vitejs.dev/guide/assets for more details on referencing assets.`
 						);
 					}
+					throw new Error(
+						`Could not locate ${file_path}. See https://vitejs.dev/guide/assets for more details on referencing assets.`
+					);
+				}
 
+				if (OPTIMIZABLE.test(url)) {
 					let image = images.get(resolved_id);
 					if (!image) {
 						image = await process(resolved_id, opts);
 						images.set(resolved_id, image);
 					}
 					s.update(node.start, node.end, img_to_picture(content, node, image));
 				} else {
-					// e.g. <img src="./foo.svg" /> => <img src={__IMPORTED_ASSET_0__} />
 					const name = '__IMPORTED_ASSET_' + imports.size + '__';
-					const { start, end } = src_attribute;
-					// update src with reference to imported asset
-					s.update(
-						is_quote(content, start - 1) ? start - 1 : start,
-						is_quote(content, end) ? end + 1 : end,
-						`{${name}}`
-					);
-					// update `enhanced:img` to `img`
-					s.update(node.start + 1, node.start + 1 + 'enhanced:img'.length, 'img');
+					const metadata = await sharp(resolved_id).metadata();
+					const new_markup = `<img ${serialize_img_attributes(content, node.attributes, {
+						src: `{${name}}`,
+						width: metadata.width || 0,
+						height: metadata.height || 0
+					})} />`;
+					s.update(node.start, node.end, new_markup);
 					imports.set(original_url, name);
 				}
 			}
@@ -175,15 +176,6 @@ export function image(opts) {
 	};
 }
 
-/**
- * @param {string} content
- * @param {number} index
- * @returns {boolean}
- */
-function is_quote(content, index) {
-	return content.charAt(index) === '"' || content.charAt(index) === "'";
-}
-
 /**
  * @param {string} resolved_id
  * @param {{

packages/enhanced-img/test/Input.svelte

@@ -45,8 +45,6 @@
 
 <enhanced:img {src} alt="attribute shorthand test" />
 
-<enhanced:img src="./foo.svg" alt="svg test" />
-
 {#each images as image}
 	<enhanced:img src={image} alt="opt-in test" />
 {/each}

packages/enhanced-img/test/Output.svelte

@@ -1,6 +1,4 @@
-<script lang="ts">	
-	import __IMPORTED_ASSET_0__ from "./foo.svg";
-
+<script lang="ts">
 	
 	import manual_image1 from './no.png';
 	
@@ -50,8 +48,6 @@
 	</picture>
 {/if}
 
-<img src={__IMPORTED_ASSET_0__} alt="svg test" />
-
 {#each images as image}
 	{#if typeof image === 'string'}
 	<img src={image.img.src} alt="opt-in test" width={image.img.w} height={image.img.h} />

packages/enhanced-img/test/preprocessor.spec.js

@@ -37,7 +37,7 @@ it('Image preprocess snapshot test', async () => {
 	// Make imports readable
 	const ouput = processed.code.replace(/import/g, '\n\timport');
 
-	expect(ouput).toMatchFileSnapshot('./Output.svelte');
+	await expect(ouput).toMatchFileSnapshot('./Output.svelte');
 });
 
 it('parses a minimized object', () => {

playgrounds/basic/package.json

@@ -22,6 +22,7 @@
 		"@sveltejs/adapter-static": "workspace:*",
 		"@sveltejs/adapter-vercel": "workspace:*",
 		"@sveltejs/amp": "workspace:*",
+		"@sveltejs/enhanced-img": "workspace:*",
 		"@sveltejs/kit": "workspace:*",
 		"@sveltejs/package": "workspace:*",
 		"@sveltejs/vite-plugin-svelte": "^5.0.1",

playgrounds/basic/src/routes/+page.svelte

@@ -7,3 +7,9 @@
 <h1>Welcome to SvelteKit</h1>
 
 2 + 2 = {data.sum}
+
+<h2>Pages:</h2>
+
+<ul>
+	<li><a href="images">images</a></li>
+</ul>

playgrounds/basic/src/routes/about/+page.svelte

@@ -0,0 +1,11 @@
+<div><a href="/">home</a></div>
+<br />
+<div>
+	<enhanced:img
+		src="./state-of-js-chart.png"
+		style="width:700px; height:auto"
+		alt="Svelte Collective"
+	/>
+</div>
+<br />
+<div><enhanced:img src="./svelte-logo.svg" alt="Svelte" /></div>