fix(MutationOptions): improve the type of onMutate (TanStack#2494)

ICodeMyOwnLife · web-flow · commit b95b86567dc5 · 2021-07-25T21:08:31.000+02:00
set the return type of onMutate as Promise&lt;TContext | undefined&gt; instead of Promise&lt;TContext&gt; | Promise&lt;undefined&gt; to make it work with async functions
diff --git a/src/core/types.ts b/src/core/types.ts
@@ -481,7 +481,7 @@ export interface MutationOptions<
   variables?: TVariables
   onMutate?: (
     variables: TVariables
-  ) => Promise<TContext> | Promise<undefined> | TContext | undefined
+  ) => Promise<TContext | undefined> | TContext | undefined
   onSuccess?: (
     data: TData,
     variables: TVariables,
diff --git a/src/react/types.ts b/src/react/types.ts
@@ -77,7 +77,7 @@ export interface UseMutationOptions<
   mutationKey?: MutationKey
   onMutate?: (
     variables: TVariables
-  ) => Promise<TContext> | Promise<undefined> | TContext | undefined
+  ) => Promise<TContext | undefined> | TContext | undefined
   onSuccess?: (
     data: TData,
     variables: TVariables,
