Best practice for dealing with mutation function that doesn't error

[glacial igloo]

Hey all,

I have a useMutation that wraps a function that returns a type like follows:

type Return = {
  status: "success";
  data: string;
} | {
  status: "error";
  errors: SomeErrorType;
};

The difficulty is I want to use React-Query's features like status, auto-error retrying, etc. To make this work, I've had to wrap the mutation function in something that checks for status === "error" and then throw an error so React-Query sees it as such. Anyone have a cleaner idea for this?

onst { status, data, isLoading, mutate } = useMutation({
        mutationFn: async () => {
            const result = await someMutationFunction();

            // If successful, return data
            if (result.status === "success") return result.data;

            // Something unexpected happened
            setError("name", { message: "Something went wrong" });
            throw new Error("Unexpected error");
        }
    });

[azure onyx]

Probably cleaner to use the onError callback to perform your setError but other than that looks fine

If there are multiple mutations like this then you could put the check for error inside a separate method e.g. throwIfErrorStatus(result) to call from any mutation

[mild pollen]

Why can’t you modify the function itself?