feat: allow providing a transform output type

playground/pages/index.vue

@@ -1,4 +1,13 @@
 <script setup lang="ts">
+import { TRPCClientError, TRPCClientErrorLike } from '@trpc/client'
+import type { inferRouterOutputs } from '@trpc/server'
+import type { AppRouter } from '@/server/trpc/routers'
+
+type RouterOutput = inferRouterOutputs<AppRouter>
+type GetTodosOutput = RouterOutput['todo']['getTodos']
+
+type ErrorOutput = TRPCClientError<AppRouter>
+
 const { $client } = useNuxtApp()
 
 const addTodo = async () => {

src/client/types.ts

@@ -50,12 +50,14 @@ type DecorateProcedure<
 > = TProcedure extends AnyQueryProcedure
   ? {
       useQuery: <
-      TData = inferTransformedProcedureOutput<TProcedure>,
-      PickKeys extends KeysOf<TData> = KeysOf<TData>,
+      ResT = inferTransformedProcedureOutput<TProcedure>,
+      DataE = TRPCClientErrorLike<TProcedure>,
+      DataT = ResT,
+      PickKeys extends KeysOf<DataT> = KeysOf<DataT>,
      >(
         input: inferProcedureInput<TProcedure>,
-        opts?: AsyncDataOptions<TData, TData, PickKeys> & { trpc?: TRPCRequestOptions },
-      ) => AsyncData<PickFrom<TData, PickKeys>, TRPCClientErrorLike<TProcedure>>,
+        opts?: AsyncDataOptions<ResT, DataT, PickKeys> & { trpc?: TRPCRequestOptions },
+      ) => AsyncData<PickFrom<DataT, PickKeys>, DataE>,
       query: Resolver<TProcedure>
     } : TProcedure extends AnyMutationProcedure ? {
       mutate: Resolver<TProcedure>