Rails PRO vs AR

what_i_have_to_do.rb

class PRO
def self.create a, b, c
  obj = build(a, b, c)
  obj.save
  obj
end

def self.build a, b, c
  Model.new params(a, b, c)
end

def params a, b, c
  {
    name: name_based_on a,
    description: description_based_on b,
    a_type: typed_based_on c
  }
end

def named_based_on a
  some_logic
end

def description_based_on b
  some_logic
end

def type_based_on c
  some_logic
end
end

# Fast tests run against params

what_i_want.rb

class PRO
def self.create a, b, c
  obj = build(a, b, c)
  obj.save
  obj
end

def self.build a, b, c
  obj = Model.new
  obj.name = name_based_on a
  obj.description = description_based_on b
  obj.a_type = type_based_on c
  obj
end
end

# Fast tests run against returned Model instance

with_repository_pattern.rb

# How pretty much everyone else does this.

class ModelBuilder
  def create a, b, c
    ModelRepository.save(build(a, b, c))
  end

  def build a, b, c
    obj = Model.new
    obj.name = name_based_on a
    obj.description = description_based_on b
    obj.a_type = type_based_on c
    obj
  end
end

class ModelRepository
  def save obj
    session.save_or_create obj
  end
end

class Model #< ActiveModel::Base <- Fuck you
  attr_accessor :name, :description, :a_type
end