1 files changed, 36 insertions, 0 deletions
diff --git a/packages/astro/src/vite-plugin-hmr-reload/index.ts b/packages/astro/src/vite-plugin-hmr-reload/index.ts
new file mode 100644
index 000000000..cf151eef6
--- /dev/null
+++ b/packages/astro/src/vite-plugin-hmr-reload/index.ts
@@ -0,0 +1,36 @@
+import type { EnvironmentModuleNode, Plugin } from 'vite';
+
+/**
+ * The very last Vite plugin to reload the browser if any SSR-only module are updated
+ * which will require a full page reload. This mimics the behaviour of Vite 5 where
+ * it used to unconditionally reload for us.
+ */
+export default function hmrReload(): Plugin {
+	return {
+		name: 'astro:hmr-reload',
+		enforce: 'post',
+		hotUpdate: {
+			order: 'post',
+			handler({ modules, server, timestamp }) {
+				if (this.environment.name !== 'ssr') return;
+
+				let hasSsrOnlyModules = false;
+
+				const invalidatedModules = new Set<EnvironmentModuleNode>();
+				for (const mod of modules) {
+					if (mod.id == null) continue;
+					const clientModule = server.environments.client.moduleGraph.getModuleById(mod.id);
+					if (clientModule != null) continue;
+
+					this.environment.moduleGraph.invalidateModule(mod, invalidatedModules, timestamp, true);
+					hasSsrOnlyModules = true;
+				}
+
+				if (hasSsrOnlyModules) {
+					server.ws.send({ type: 'full-reload' });
+					return [];
+				}
+			},
+		},
+	};
+}