class Protobuf::Visitor::CreateDescriptorVisitor

def add_option(name, value)
  options =
    case current_descriptor
    when Google::Protobuf::FileDescriptorProto then
      Google::Protobuf::FileOptions.new
    when Google::Protobuf::DescriptorProto then
      Google::Protobuf::MessageOptions.new
    when Google::Protobuf::FieldDescriptorProto then
      Google::Protobuf::FieldOptions.new
    when Google::Protobuf::EnumDescriptorProto then
      Google::Protobuf::EnumOptions.new
    when Google::Protobuf::EnumValueDescriptorProto then
      Google::Protobuf::EnumValueOptions.new
    when Google::Protobuf::ServiceDescriptorProto then
      Google::Protobuf::ServiceOptions.new
    when Google::Protobuf::MethodDescriptorProto then
      Google::Protobuf::MethodOptions.new
    else
      raise ArgumentError, 'Invalid context'
    end
  #TODO how should options be handled?
  #current_descriptor.options << option
end