ROM mapper issue

rom_mapper_issue.rb

#!/usr/bin/ruby

require 'rom'

configuration = ROM::Configuration.new(:memory, 'memory://test')

class AppointmentInfoRepository < ROM::Repository::Root
  root :appointment_info

  commands :create
end

class AppointmentInfo < ROM::Relation[:memory]
  schema do
    attribute :date, Types::String, read: Types::Form::Date
  end
end

class CreateAppointmentInfo < ROM::Commands::Create[:memory]
  relation :appointment_info
  register_as :create
  result :one
end

class AppointmentMapper < ROM::Mapper
  relation :appointment_info
  register_as :appointment_mapper
end

class MyMapper < ROM::Mapper
  relation :appointment_info
  register_as :my_mapper

  attribute(:date) { |t| t.strftime('%m/%d/%Y') }
  attribute(:start_time, from: :time)
end


configuration.register_relation(AppointmentInfo)
configuration.register_command(CreateAppointmentInfo)
configuration.register_mapper(AppointmentMapper)
configuration.register_mapper(MyMapper)

container = ROM.container(configuration)

appt_info = container.relations[:appointment_info]
create_appt_info = appt_info.command(:create)
puts create_appt_info.call(date: Date.today).to_h
puts appt_info.map_with(:my_mapper).to_a
puts appt_info.map_with(:appointment_mapper).to_a