From 1c3a05263c61de697361a70080eca316a69b4639 Mon Sep 17 00:00:00 2001
From: Wonsuk Choi <sukvvon@gmail.com>
Date: Thu, 10 Sep 2026 08:13:37 +0900
Subject: [PATCH 1/2] test(vue-query/useQuery): add type test for inferring the
 result type from a generic 'queryFn'

---
 .../src/__tests__/useQuery.test-d.ts          | 20 +++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/packages/vue-query/src/__tests__/useQuery.test-d.ts b/packages/vue-query/src/__tests__/useQuery.test-d.ts
index a9b0125ab0..c92c6947d9 100644
--- a/packages/vue-query/src/__tests__/useQuery.test-d.ts
+++ b/packages/vue-query/src/__tests__/useQuery.test-d.ts
@@ -153,6 +153,26 @@ describe('useQuery', () => {
     })
   })
 
+  describe('generic queryFn', () => {
+    it('should infer the result type from a generic query function', () => {
+      const key = queryKey()
+
+      function queryFn<T = string>(): Promise<T> {
+        return Promise.resolve({} as T)
+      }
+
+      const query = reactive(
+        useQuery({
+          queryKey: key,
+          queryFn: () => queryFn(),
+        }),
+      )
+
+      expectTypeOf(query.data).toEqualTypeOf<string | undefined>()
+      expectTypeOf(query.error).toEqualTypeOf<Error | null>()
+    })
+  })
+
   describe('generic queryKey inference (#8199)', () => {
     it('should not error when wrapping useQuery in a composable that propagates a generic type to the queryKey', () => {
       const basket = { fruit: 'apple', vegetable: 'broccoli' } as const

From b0b65812da348945052b61e86cf121dc8381c4c1 Mon Sep 17 00:00:00 2001
From: Wonsuk Choi <sukvvon@gmail.com>
Date: Thu, 10 Sep 2026 08:13:37 +0900
Subject: [PATCH 2/2] test(svelte-query/createQuery): add type test for
 inferring the result type from a generic 'queryFn'

---
 .../tests/createQuery/createQuery.test-d.ts    | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/packages/svelte-query/tests/createQuery/createQuery.test-d.ts b/packages/svelte-query/tests/createQuery/createQuery.test-d.ts
index 8b6590b334..603d89a5f1 100644
--- a/packages/svelte-query/tests/createQuery/createQuery.test-d.ts
+++ b/packages/svelte-query/tests/createQuery/createQuery.test-d.ts
@@ -96,4 +96,22 @@ describe('createQuery', () => {
       })
     })
   })
+
+  describe('generic queryFn', () => {
+    it('should infer the result type from a generic query function', () => {
+      const key = queryKey()
+
+      function queryFn<T = string>(): Promise<T> {
+        return Promise.resolve({} as T)
+      }
+
+      const query = createQuery(() => ({
+        queryKey: key,
+        queryFn: () => queryFn(),
+      }))
+
+      expectTypeOf(query.data).toEqualTypeOf<string | undefined>()
+      expectTypeOf(query.error).toEqualTypeOf<Error | null>()
+    })
+  })
 })