From f1fb2344e2cd818f20391373b334c499f450fa7c Mon Sep 17 00:00:00 2001
From: Lachlan Collins <1667261+lachlancollins@users.noreply.github.com>
Date: Sat, 20 Jul 2024 20:34:30 +1000
Subject: [PATCH] Fix createQuery types

---
 packages/svelte-query/src/createQuery.ts      | 15 +++--
 .../createQueries/createQueries.test-d.ts     | 44 +++++++++++++
 .../tests/createQuery/createQuery.test-d.ts   | 65 +++++++++++++++++++
 3 files changed, 119 insertions(+), 5 deletions(-)
 create mode 100644 packages/svelte-query/tests/createQuery/createQuery.test-d.ts

diff --git a/packages/svelte-query/src/createQuery.ts b/packages/svelte-query/src/createQuery.ts
index 08417d54c2..32bf45e394 100644
--- a/packages/svelte-query/src/createQuery.ts
+++ b/packages/svelte-query/src/createQuery.ts
@@ -19,10 +19,10 @@ export function createQuery<
   TQueryKey extends QueryKey = QueryKey,
 >(
   options: StoreOrVal<
-    UndefinedInitialDataOptions<TQueryFnData, TError, TData, TQueryKey>
+    DefinedInitialDataOptions<TQueryFnData, TError, TData, TQueryKey>
   >,
   queryClient?: QueryClient,
-): CreateQueryResult<TData, TError>
+): DefinedCreateQueryResult<TData, TError>
 
 export function createQuery<
   TQueryFnData = unknown,
@@ -31,13 +31,13 @@ export function createQuery<
   TQueryKey extends QueryKey = QueryKey,
 >(
   options: StoreOrVal<
-    DefinedInitialDataOptions<TQueryFnData, TError, TData, TQueryKey>
+    UndefinedInitialDataOptions<TQueryFnData, TError, TData, TQueryKey>
   >,
   queryClient?: QueryClient,
-): DefinedCreateQueryResult<TData, TError>
+): CreateQueryResult<TData, TError>
 
 export function createQuery<
-  TQueryFnData,
+  TQueryFnData = unknown,
   TError = DefaultError,
   TData = TQueryFnData,
   TQueryKey extends QueryKey = QueryKey,
@@ -46,6 +46,11 @@ export function createQuery<
     CreateQueryOptions<TQueryFnData, TError, TData, TQueryKey>
   >,
   queryClient?: QueryClient,
+): CreateQueryResult<TData, TError>
+
+export function createQuery(
+  options: StoreOrVal<CreateQueryOptions>,
+  queryClient?: QueryClient,
 ) {
   return createBaseQuery(options, QueryObserver, queryClient)
 }
diff --git a/packages/svelte-query/tests/createQueries/createQueries.test-d.ts b/packages/svelte-query/tests/createQueries/createQueries.test-d.ts
index 32721b2f49..0f3881330a 100644
--- a/packages/svelte-query/tests/createQueries/createQueries.test-d.ts
+++ b/packages/svelte-query/tests/createQueries/createQueries.test-d.ts
@@ -1,6 +1,9 @@
 import { describe, expectTypeOf, test } from 'vitest'
 import { get } from 'svelte/store'
+import { skipToken } from '@tanstack/query-core'
 import { createQueries, queryOptions } from '../../src/index'
+import type { OmitKeyof, QueryObserverResult } from '@tanstack/query-core'
+import type { CreateQueryOptions } from '../../src/index'
 
 describe('createQueries', () => {
   test('TData should be defined when passed through queryOptions', () => {
@@ -21,4 +24,45 @@ describe('createQueries', () => {
 
     expectTypeOf(data).toEqualTypeOf<{ wow: boolean }>()
   })
+
+  test('Allow custom hooks using UseQueryOptions', () => {
+    type Data = string
+
+    const useCustomQueries = (
+      options?: OmitKeyof<CreateQueryOptions<Data>, 'queryKey' | 'queryFn'>,
+    ) => {
+      return createQueries({
+        queries: [
+          {
+            ...options,
+            queryKey: ['todos-key'],
+            queryFn: () => Promise.resolve('data'),
+          },
+        ],
+      })
+    }
+
+    const query = useCustomQueries()
+    const data = get(query)[0].data
+
+    expectTypeOf(data).toEqualTypeOf<Data | undefined>()
+  })
+
+  test('TData should have correct type when conditional skipToken is passed', () => {
+    const queryResults = createQueries({
+      queries: [
+        {
+          queryKey: ['withSkipToken'],
+          queryFn: Math.random() > 0.5 ? skipToken : () => Promise.resolve(5),
+        },
+      ],
+    })
+
+    const firstResult = get(queryResults)[0]
+
+    expectTypeOf(firstResult).toEqualTypeOf<
+      QueryObserverResult<number, Error>
+    >()
+    expectTypeOf(firstResult.data).toEqualTypeOf<number | undefined>()
+  })
 })
diff --git a/packages/svelte-query/tests/createQuery/createQuery.test-d.ts b/packages/svelte-query/tests/createQuery/createQuery.test-d.ts
new file mode 100644
index 0000000000..f2931340e9
--- /dev/null
+++ b/packages/svelte-query/tests/createQuery/createQuery.test-d.ts
@@ -0,0 +1,65 @@
+import { describe, expectTypeOf, test } from 'vitest'
+import { get } from 'svelte/store'
+import { createQuery, queryOptions } from '../../src/index'
+import type { OmitKeyof } from '@tanstack/query-core'
+import type { CreateQueryOptions } from '../../src/index'
+
+describe('createQuery', () => {
+  test('TData should always be defined when initialData is provided as an object', () => {
+    const query = createQuery({
+      queryKey: ['key'],
+      queryFn: () => ({ wow: true }),
+      initialData: { wow: true },
+    })
+
+    expectTypeOf(get(query).data).toEqualTypeOf<{ wow: boolean }>()
+  })
+
+  test('TData should be defined when passed through queryOptions', () => {
+    const options = queryOptions({
+      queryKey: ['key'],
+      queryFn: () => {
+        return {
+          wow: true,
+        }
+      },
+      initialData: {
+        wow: true,
+      },
+    })
+    const query = createQuery(options)
+
+    expectTypeOf(get(query).data).toEqualTypeOf<{ wow: boolean }>()
+  })
+
+  test('TData should have undefined in the union when initialData is NOT provided', () => {
+    const query = createQuery({
+      queryKey: ['key'],
+      queryFn: () => {
+        return {
+          wow: true,
+        }
+      },
+    })
+
+    expectTypeOf(get(query).data).toEqualTypeOf<{ wow: boolean } | undefined>()
+  })
+
+  test('Allow custom hooks using CreateQueryOptions', () => {
+    type Data = string
+
+    const useCustomQuery = (
+      options?: OmitKeyof<CreateQueryOptions<Data>, 'queryKey' | 'queryFn'>,
+    ) => {
+      return createQuery({
+        ...options,
+        queryKey: ['todos-key'],
+        queryFn: () => Promise.resolve('data'),
+      })
+    }
+
+    const query = useCustomQuery()
+
+    expectTypeOf(get(query).data).toEqualTypeOf<Data | undefined>()
+  })
+})