HMR hoisted scripts (#3336)

* HMR hoisted scripts

* Add to the dep graph

* Remove example change

* Adds changeset

* Fix markdown test

.changeset/happy-wasps-check.md

@@ -0,0 +1,5 @@
+---
+'astro': patch
+---
+
+Fixes HMR of hoisted script tags

packages/astro/src/vite-plugin-astro/hmr.ts

@@ -68,6 +68,7 @@ export async function handleHotUpdate(ctx: HmrContext, config: AstroConfig, logg
 			filtered.add(mod);
 			files.add(mod.file);
 		}
+		
 		for (const imp of mod.importers) {
 			if (imp.file && isCached(config, imp.file)) {
 				filtered.add(imp);
@@ -85,6 +86,15 @@ export async function handleHotUpdate(ctx: HmrContext, config: AstroConfig, logg
 	// Bugfix: sometimes style URLs get normalized and end with `lang.css=`
 	// These will cause full reloads, so filter them out here
 	const mods = ctx.modules.filter((m) => !m.url.endsWith('='));
+
+	// Add hoisted scripts so these get invalidated
+	for(const mod of mods) {
+		for(const imp of mod.importedModules) {
+			if(imp.id?.includes('?astro&type=script')) {
+				mods.push(imp);
+			}
+		}
+	}
 	const isSelfAccepting = mods.every((m) => m.isSelfAccepting || m.url.endsWith('.svelte'));
 
 	const file = ctx.file.replace(config.root.pathname, '/');

packages/astro/src/vite-plugin-astro/index.ts

@@ -126,6 +126,12 @@ export default function astro({ config, logging }: AstroPluginOptions): vite.Plu
 					if (typeof query.index === 'undefined') {
 						throw new Error(`Requests for hoisted scripts must include an index`);
 					}
+					// HMR hoisted script only exists to make them appear in the module graph.
+					if(opts?.ssr) {
+						return {
+							code: `/* client hoisted script, empty in SSR: ${id} */`
+						};
+					}
 
 					const transformResult = await cachedCompilation(config, filename, source, viteTransform, {
 						ssr: Boolean(opts?.ssr),
@@ -182,17 +188,28 @@ export default function astro({ config, logging }: AstroPluginOptions): vite.Plu
 					while ((match = pattern.exec(metadata)?.[1])) {
 						deps.add(match);
 					}
-					// // import.meta.hot.accept(["${id}", "${Array.from(deps).join('","')}"], (...mods) => mods);
-					// We need to be self-accepting, AND
-					// we need an explicity array of deps to track changes for SSR-only components
+
+					let i = 0;
+					while(i < transformResult.scripts.length) {
+						deps.add(`${id}?astro&type=script&index=${i}`);
+						SUFFIX += `import "${id}?astro&type=script&index=${i}";`;
+						i++;
+					}
+
+					// We only need to define deps if there are any
+					if(deps.size > 1) {
+						SUFFIX += `\nif(import.meta.hot) import.meta.hot.accept(["${id}", "${Array.from(deps).join('","')}"], (...mods) => mods);`
+					} else {
 						SUFFIX += `\nif (import.meta.hot) {
 							import.meta.hot.accept(mod => mod);
 						}`;
 					}
+				}
 				// Add handling to inject scripts into each page JS bundle, if needed.
 				if (isPage) {
 					SUFFIX += `\nimport "${PAGE_SSR_SCRIPT_ID}";`;
 				}
+				
 				return {
 					code: `${code}${SUFFIX}`,
 					map,
@@ -260,7 +277,7 @@ export default function astro({ config, logging }: AstroPluginOptions): vite.Plu
 		},
 		async handleHotUpdate(context) {
 			if (context.server.config.isProduction) return;
-			return handleHotUpdate(context, config, logging);
+			return handleHotUpdate.call(this, context, config, logging);
 		},
 	};
 }

packages/astro/test/astro-markdown-css.test.js

@@ -34,11 +34,12 @@ describe('Imported markdown CSS', function () {
 	});
 	describe('dev', () => {
 		let devServer;
+		let html;
 		let $;
 
 		before(async () => {
 			devServer = await fixture.startDevServer();
-			const html = await fixture.fetch('/').then((res) => res.text());
+			html = await fixture.fetch('/').then((res) => res.text());
 			$ = cheerio.load(html);
 		});