factory_with_fake_rom.rb

module ROM
end

require "dry/struct"
require "dry/types"
require "rom-factory"

module Types
  include Dry::Types.module
end

class User < Dry::Struct
  constructor_type :strict_with_defaults

  attribute :id, String
  attribute :name, Types.Instance(String)
  attribute :email, Types.Instance(String)
end

FakeAttribute = Struct.new(:name)

class FakeRelation
  def initialize(name, klass)
    @klass = klass
    @attributes = klass.schema.map { |name, _| FakeAttribute.new(name) }
  end

  def schema
    self
  end

  def attributes
    @attributes
  end

  def with(*)
    self
  end

  def combine(*)
    self
  end

  def mapper
    self
  end

  def model
    @klass
  end

  def reject(*)
    @attributes
  end

  def primary_key
    :id
  end
end

class FakeRelations
  def [](name)
    FakeRelation.new(name, User)
  end
end

class RomFake
  def relations
    FakeRelations.new
  end
end

Factory = ROM::Factory.configure do |config|
  config.rom = RomFake.new
end

Factory.define(:user) do |f|
  f.name { fake(:name, :first_name) }
  f.sequence :email do |n|
    "janjiss#{n}@gmail.com"
  end
end

p Factory.structs[:user]
p Factory.structs[:user]
p Factory.structs[:user]

# #<User id=1 name="Krystal" email="janjiss1@gmail.com">
# #<User id=2 name="Jeff" email="janjiss2@gmail.com">
# #<User id=3 name="Genoveva" email="janjiss3@gmail.com">