return nil, nil, fmt.Errorf("Unexpected returned value from compareListValuesAtIndex: %v and %v", originalV, modifiedV)
		}
	}

	return addList, deduplicateScalars(deletionList), nil
}

// If first return value is non-nil, list1 contains an element not present in list2
// If second return value is non-nil, list2 contains an element not present in list1