fix(svelte-query): infer query data type in queryOptions (#7537)

* fix(svelte-query): infer query data type in queryOptions

* test(svelte-query): add tests for queryOptions type inference

packages/svelte-query/src/__tests__/queryOptions.test.ts

@@ -0,0 +1,146 @@
+import { QueryClient, dataTagSymbol, skipToken } from '@tanstack/query-core'
+import { describe, expectTypeOf, it } from 'vitest'
+import { queryOptions } from '../queryOptions'
+
+describe('queryOptions', () => {
+  it('should not allow excess properties', () => {
+    queryOptions({
+      queryKey: ['key'],
+      queryFn: () => Promise.resolve(5),
+      // @ts-expect-error this is a good error, because stallTime does not exist!
+      stallTime: 1000,
+    })
+  })
+
+  it('should infer types for callbacks', () => {
+    queryOptions({
+      queryKey: ['key'],
+      queryFn: () => Promise.resolve(5),
+      staleTime: 1000,
+      select: (data) => {
+        expectTypeOf(data).toEqualTypeOf<number>()
+      },
+    })
+  })
+
+  it('should work when passed to fetchQuery', async () => {
+    const options = queryOptions({
+      queryKey: ['key'],
+      queryFn: () => Promise.resolve(5),
+    })
+
+    const data = await new QueryClient().fetchQuery(options)
+    expectTypeOf(data).toEqualTypeOf<number>()
+  })
+
+  it('should tag the queryKey with the result type of the QueryFn', () => {
+    const { queryKey } = queryOptions({
+      queryKey: ['key'],
+      queryFn: () => Promise.resolve(5),
+    })
+
+    expectTypeOf(queryKey[dataTagSymbol]).toEqualTypeOf<number>()
+  })
+
+  it('should tag the queryKey even if no promise is returned', () => {
+    const { queryKey } = queryOptions({
+      queryKey: ['key'],
+      queryFn: () => 5,
+    })
+
+    expectTypeOf(queryKey[dataTagSymbol]).toEqualTypeOf<number>()
+  })
+
+  it('should tag the queryKey with unknown if there is no queryFn', () => {
+    const { queryKey } = queryOptions({
+      queryKey: ['key'],
+    })
+
+    expectTypeOf(queryKey[dataTagSymbol]).toEqualTypeOf<unknown>()
+  })
+
+  it('should tag the queryKey with the result type of the QueryFn if select is used', () => {
+    const { queryKey } = queryOptions({
+      queryKey: ['key'],
+      queryFn: () => Promise.resolve(5),
+      select: (data) => data.toString(),
+    })
+
+    expectTypeOf(queryKey[dataTagSymbol]).toEqualTypeOf<number>()
+  })
+
+  it('should return the proper type when passed to getQueryData', () => {
+    const { queryKey } = queryOptions({
+      queryKey: ['key'],
+      queryFn: () => Promise.resolve(5),
+    })
+
+    const queryClient = new QueryClient()
+    const data = queryClient.getQueryData(queryKey)
+    expectTypeOf(data).toEqualTypeOf<number | undefined>()
+  })
+
+  it('should return the proper type when passed to getQueryState', () => {
+    const { queryKey } = queryOptions({
+      queryKey: ['key'],
+      queryFn: () => Promise.resolve(5),
+    })
+
+    const queryClient = new QueryClient()
+    const state = queryClient.getQueryState(queryKey)
+    expectTypeOf(state?.data).toEqualTypeOf<number | undefined>()
+  })
+
+  it('should properly type updaterFn when passed to setQueryData', () => {
+    const { queryKey } = queryOptions({
+      queryKey: ['key'],
+      queryFn: () => Promise.resolve(5),
+    })
+
+    const queryClient = new QueryClient()
+    const data = queryClient.setQueryData(queryKey, (prev) => {
+      expectTypeOf(prev).toEqualTypeOf<number | undefined>()
+      return prev
+    })
+    expectTypeOf(data).toEqualTypeOf<number | undefined>()
+  })
+
+  it('should properly type value when passed to setQueryData', () => {
+    const { queryKey } = queryOptions({
+      queryKey: ['key'],
+      queryFn: () => Promise.resolve(5),
+    })
+
+    const queryClient = new QueryClient()
+
+    // @ts-expect-error value should be a number
+    queryClient.setQueryData(queryKey, '5')
+    // @ts-expect-error value should be a number
+    queryClient.setQueryData(queryKey, () => '5')
+
+    const data = queryClient.setQueryData(queryKey, 5)
+    expectTypeOf(data).toEqualTypeOf<number | undefined>()
+  })
+
+  it('should infer even if there is a conditional skipToken', () => {
+    const options = queryOptions({
+      queryKey: ['key'],
+      queryFn: Math.random() > 0.5 ? skipToken : () => Promise.resolve(5),
+    })
+
+    const queryClient = new QueryClient()
+    const data = queryClient.getQueryData(options.queryKey)
+    expectTypeOf(data).toEqualTypeOf<number | undefined>()
+  })
+
+  it('should infer to unknown if we disable a query with just a skipToken', () => {
+    const options = queryOptions({
+      queryKey: ['key'],
+      queryFn: skipToken,
+    })
+
+    const queryClient = new QueryClient()
+    const data = queryClient.getQueryData(options.queryKey)
+    expectTypeOf(data).toEqualTypeOf<unknown>()
+  })
+})

packages/svelte-query/src/queryOptions.ts

@@ -1,4 +1,4 @@
-import type { DefaultError, QueryKey } from '@tanstack/query-core'
+import type { DataTag, DefaultError, QueryKey } from '@tanstack/query-core'
 import type { CreateQueryOptions } from './types'
 
 export type UndefinedInitialDataOptions<
@@ -30,7 +30,9 @@ export function queryOptions<
   TQueryKey extends QueryKey = QueryKey,
 >(
   options: UndefinedInitialDataOptions<TQueryFnData, TError, TData, TQueryKey>,
-): UndefinedInitialDataOptions<TQueryFnData, TError, TData, TQueryKey>
+): UndefinedInitialDataOptions<TQueryFnData, TError, TData, TQueryKey> & {
+  queryKey: DataTag<TQueryKey, TQueryFnData>
+}
 
 export function queryOptions<
   TQueryFnData = unknown,
@@ -39,7 +41,9 @@ export function queryOptions<
   TQueryKey extends QueryKey = QueryKey,
 >(
   options: DefinedInitialDataOptions<TQueryFnData, TError, TData, TQueryKey>,
-): DefinedInitialDataOptions<TQueryFnData, TError, TData, TQueryKey>
+): DefinedInitialDataOptions<TQueryFnData, TError, TData, TQueryKey> & {
+  queryKey: DataTag<TQueryKey, TQueryFnData>
+}
 
 export function queryOptions(options: unknown) {
   return options