From 775d072e8a2af9566b0b0250f61069aaed21d4a8 Mon Sep 17 00:00:00 2001
From: "shiwoo.park" <custardcream@kakao.com>
Date: Wed, 16 Apr 2025 11:53:30 +0900
Subject: [PATCH 1/4] fix(query-core): fix setQueryData type inference in typed
 contexts

---
 packages/query-core/src/queryClient.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/query-core/src/queryClient.ts b/packages/query-core/src/queryClient.ts
index ad920601fc..3406bbf7d2 100644
--- a/packages/query-core/src/queryClient.ts
+++ b/packages/query-core/src/queryClient.ts
@@ -185,7 +185,7 @@ export class QueryClient {
       NoInfer<TInferredQueryFnData> | undefined
     >,
     options?: SetDataOptions,
-  ): TInferredQueryFnData | undefined {
+  ): NoInfer<TInferredQueryFnData> | undefined {
     const defaultedOptions = this.defaultQueryOptions<
       any,
       any,

From 53a2d7934508b46c026f3a192c3ed0a75e15a7e0 Mon Sep 17 00:00:00 2001
From: "shiwoo.park" <custardcream@kakao.com>
Date: Wed, 16 Apr 2025 11:53:58 +0900
Subject: [PATCH 2/4] test(query-core): add test case for setQueryData type
 inference in functions

---
 .../src/__tests__/queryClient.test-d.tsx      | 38 +++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/packages/query-core/src/__tests__/queryClient.test-d.tsx b/packages/query-core/src/__tests__/queryClient.test-d.tsx
index e06d5829bd..c9d953a973 100644
--- a/packages/query-core/src/__tests__/queryClient.test-d.tsx
+++ b/packages/query-core/src/__tests__/queryClient.test-d.tsx
@@ -113,6 +113,19 @@ describe('setQueryData', () => {
 
     expectTypeOf(data).toEqualTypeOf<string | undefined>()
   })
+
+  it('should preserve updater parameter type inference when used in functions with explicit return types', () => {
+    const queryKey = ['key'] as DataTag<Array<string>, number>
+    const queryClient = new QueryClient()
+
+    // Simulate usage inside a function with explicit return type
+    // The outer function returns 'unknown' but this shouldn't affect the updater's type inference
+    ;(() =>
+      queryClient.setQueryData(queryKey, (data) => {
+        expectTypeOf(data).toEqualTypeOf<number | undefined>()
+        return data
+      })) satisfies () => unknown
+  })
 })
 
 describe('getQueryState', () => {
@@ -590,3 +603,28 @@ describe('resetQueries', () => {
     })
   })
 })
+type SuccessCallback = () => unknown
+it('should infer types correctly with expression body arrow functions', () => {
+  const queryKey = ['key'] as DataTag<Array<string>, number>
+  const queryClient = new QueryClient()
+
+  // @ts-expect-error
+  const callbackTest: SuccessCallback = () =>
+    queryClient.setQueryData(queryKey, (data) => {
+      expectTypeOf(data).toEqualTypeOf<number | undefined>()
+      return data
+    })
+})
+
+it('should infer types correctly with block body arrow functions', () => {
+  const queryKey = ['key'] as DataTag<Array<string>, number>
+  const queryClient = new QueryClient()
+
+  // @ts-expect-error
+  const callbackTest2: SuccessCallback = () => {
+    queryClient.setQueryData(queryKey, (data) => {
+      expectTypeOf(data).toEqualTypeOf<number | undefined>()
+      return data
+    })
+  }
+})

From b5c6dde913b840066eee0ee60f7ae5835ee41aac Mon Sep 17 00:00:00 2001
From: "shiwoo.park" <custardcream@kakao.com>
Date: Wed, 16 Apr 2025 12:17:54 +0900
Subject: [PATCH 3/4] fix(vue-query): fix setQueryData type inference in typed
 contexts

---
 packages/vue-query/src/queryClient.ts | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/packages/vue-query/src/queryClient.ts b/packages/vue-query/src/queryClient.ts
index ca0fe3953d..dc0bff131d 100644
--- a/packages/vue-query/src/queryClient.ts
+++ b/packages/vue-query/src/queryClient.ts
@@ -114,17 +114,17 @@ export class QueryClient extends QC {
       NoInfer<TInferredQueryFnData> | undefined
     >,
     options?: MaybeRefDeep<SetDataOptions>,
-  ): TInferredQueryFnData | undefined
+  ): NoInfer<TInferredQueryFnData> | undefined
   setQueryData<TQueryFnData, TData = NoUnknown<TQueryFnData>>(
     queryKey: MaybeRefDeep<QueryKey>,
     updater: Updater<NoInfer<TData> | undefined, NoInfer<TData> | undefined>,
     options?: MaybeRefDeep<SetDataOptions>,
-  ): TData | undefined
+  ): NoInfer<TData> | undefined
   setQueryData<TData>(
     queryKey: MaybeRefDeep<QueryKey>,
     updater: Updater<TData | undefined, TData | undefined>,
     options: MaybeRefDeep<SetDataOptions> = {},
-  ): TData | undefined {
+  ): NoInfer<TData> | undefined {
     return super.setQueryData(
       cloneDeepUnref(queryKey),
       updater,

From 7c34847bb101665a0ef9363b355b50be8c18cbaf Mon Sep 17 00:00:00 2001
From: "shiwoo.park" <custardcream@kakao.com>
Date: Wed, 16 Apr 2025 12:20:19 +0900
Subject: [PATCH 4/4] test(vue-query): add test case for setQueryData type
 inference in functions

---
 .../vue-query/src/__tests__/queryClient.test-d.ts   | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/packages/vue-query/src/__tests__/queryClient.test-d.ts b/packages/vue-query/src/__tests__/queryClient.test-d.ts
index fbfdd02a7a..ae50680d34 100644
--- a/packages/vue-query/src/__tests__/queryClient.test-d.ts
+++ b/packages/vue-query/src/__tests__/queryClient.test-d.ts
@@ -96,6 +96,19 @@ describe('setQueryData', () => {
 
     expectTypeOf(data).toEqualTypeOf<string | undefined>()
   })
+
+  it('should preserve updater parameter type inference when used in functions with explicit return types', () => {
+    const queryKey = ['key'] as DataTag<Array<string>, number>
+    const queryClient = new QueryClient()
+
+    // Simulate usage inside a function with explicit return type
+    // The outer function returns 'unknown' but this shouldn't affect the updater's type inference
+    ;(() =>
+      queryClient.setQueryData(queryKey, (data) => {
+        expectTypeOf(data).toEqualTypeOf<number | undefined>()
+        return data
+      })) satisfies () => unknown
+  })
 })
 
 describe('fetchInfiniteQuery', () => {