From 6a19aa79f71a3c5445100266be7ba6bb014ebc30 Mon Sep 17 00:00:00 2001
From: Daniel Roe <daniel@roe.dev>
Date: Fri, 14 Jun 2024 23:11:25 +0100
Subject: [PATCH] fix(nuxt): warn when async data doesn't return a value
 (#27599)

---
 packages/nuxt/src/app/composables/asyncData.ts | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/packages/nuxt/src/app/composables/asyncData.ts b/packages/nuxt/src/app/composables/asyncData.ts
index 8ca773a338..4808d4d6c8 100644
--- a/packages/nuxt/src/app/composables/asyncData.ts
+++ b/packages/nuxt/src/app/composables/asyncData.ts
@@ -311,6 +311,11 @@ export function useAsyncData<
           result = pick(result as any, options.pick) as DataT
         }
 
+        if (import.meta.dev && import.meta.server && !result) {
+          // @ts-expect-error private property
+          console.warn(`[nuxt] \`${options._functionName || 'useAsyncData'}\` should return a value that is not \`null\` or \`undefined\` or the request may be duplicated on the client side.`)
+        }
+
         nuxtApp.payload.data[key] = result
 
         asyncData.data.value = result