factory_helper.rb

module Test #:nodoc:
  module Unit #:nodoc:
    class TestCase #:nodoc:
      class << self
        def factories(*names)
          names.each { |name| load_factory(name) }
        end
        
        private
          def load_factory(name)
            module_eval <<-EVAL, __FILE__, __LINE__
              require 'factories/#{name}_factory'
              include #{name.to_s.camelize}Factory
            EVAL
          end
      end
    end
  end
end

people_factory.rb

module PeopleFactory
  def get_person_mock(options = {})
    Person.new({ :id => 1, :first_name => 'Larry', :last_name => 'Marburger' }.merge(options))
  end
end

test_helper.rb

class Test::Unit::TestCase
  factories :people
end