Typing error with transformErrorResponse

[berdyshev]

Hi.
When I use the transformErrorResponse I can provide custom error type returned from this method.
But it still doesn't infered when the mutation is called. So the result of calling mutation would still be { data: ResultType } | { error: FetchBaseQueryError | SerializedError } while it should be something like ReturnType<typeof transformErrorResponse>.

Yes, I can write a guard for it, but this guard will allow a type other than my custom.

if (isMyCustomError(result.error)) {
  // handle typed error
} else {
   // here result.error should have `never` type, but it won't
}

Also, I can cast the type (like, result.error as MyCustomError) but this not a good solution.

So, my question here: why the type in not infered from tranformErrorResponse or am I missing something?