feat: add trpc inference helpers

Author: juliusmarminge

template/addons/trpc/utils.ts

@@ -5,6 +5,21 @@ import { createReactQueryHooks } from "@trpc/react";
 export const trpc = createReactQueryHooks<AppRouter>();
 
 /**
- * Check out tRPC docs for Inference Helpers
- * https://trpc.io/docs/infer-types#inference-helpers
+ * This is a helper method to infer the output of a query resolver
+ * @example type HelloOutput = inferQueryOutput<'hello'>
  */
+export type inferQueryOutput<
+  TRouteKey extends keyof AppRouter["_def"]["queries"],
+> = inferProcedureOutput<AppRouter["_def"]["queries"][TRouteKey]>;
+
+export type inferQueryInput<
+  TRouteKey extends keyof AppRouter["_def"]["queries"],
+> = inferProcedureInput<AppRouter["_def"]["queries"][TRouteKey]>;
+
+export type inferMutationOutput<
+  TRouteKey extends keyof AppRouter["_def"]["mutations"],
+> = inferProcedureOutput<AppRouter["_def"]["mutations"][TRouteKey]>;
+
+export type inferMutationInput<
+  TRouteKey extends keyof AppRouter["_def"]["mutations"],
+> = inferProcedureInput<AppRouter["_def"]["mutations"][TRouteKey]>;