fix: adjust missing inner content warning (#11394)

Author: ignatiusmb

.changeset/giant-planets-sing.md

@@ -0,0 +1,5 @@
+---
+"@sveltejs/kit": patch
+---
+
+fix: adjust missing inner content warning

packages/kit/src/exports/vite/index.js

@@ -105,10 +105,14 @@ const warning_preprocessor = {
 		if (!filename) return;
 
 		const basename = path.basename(filename);
-		if (basename.startsWith('+layout.') && !content.includes('<slot')) {
+		const has_children =
+			content.includes('<slot') || (isSvelte5Plus() && content.includes('{@render'));
+
+		if (basename.startsWith('+layout.') && !has_children) {
 			const message =
 				`\n${colors.bold().red(path.relative('.', filename))}\n` +
-				'`<slot />` missing — inner content will not be rendered';
+				`\`<slot />\`${isSvelte5Plus() ? ' or `{@render ...}` tag' : ''}` +
+				' missing — inner content will not be rendered';
 
 			if (!warned.has(message)) {
 				console.log(message);