Creating some class during tests (STI)

Question

I have a class

Gate < ActiveRecord::Base
  self.inheritance_column = :kindof
# some methods
end
#  and derived
MoneyHaters < Gate
# some overloaded methods
end

with type column :kindof for STI.

Durning tests I want to create a 2-3 childs. Mainly because each derived class must be unique in the app. Like that:

factory :gate do
  before(:create) do
    gate_name  = FFaker::Company.name.gsub( /\s+/,'' )
    gate_class_name = gate_name.singularize.classify
  end

  name { gate_name }

  # I want that next class will be declared in App namespace, like all others.
  gate_class  = Class.new(Gate) do
    def comission_in(amount)
      amount * 0.01 + 5
    end
    def comission_out(amount)
      amount * 0.02 + 5
    end
  end
  Object.const_set( gate_class_name, gate_class )

  type { gate_class_name }
  country { FFaker::Address.country_code }
end

Code gave me error when ran with rspec in line "Object.const_set"

TypeError: #<FactoryGirl::Declaration::Implicit:0x00000006a1af30 @name=:gate_class_name, @ignored=false, @factory=#<FactoryGirl::Definition:0x00000006ed6df8 @declarations=#<FactoryGirl::DeclarationList:0x00000006ed6dd0 @declarations=[#<FactoryGirl::Declaration::Dynamic:0x00000006ed6998 @name=:name, @ignored=false, @block=#<Proc:0x00000006ed69c0@[skipped]>>, #<FactoryGirl::Declaration::Implicit:0x00000006a1af30 ...>], @name=:gate, @overridable=false>, @callbacks=[#<FactoryGirl::Callback:0x00000006ed6a38 @name=:before_create, @block=#<Proc:0x00000006ed6ba0@[skipped]>>], @defined_traits=#<Set: {}>, @to_create=nil, @base_traits=[], @additional_traits=[], @constructor=nil, @attributes=nil, @compiled=false>> is not a symbol nor a string

but works ok in rails console

Usually I call FactoryGirl factories for creating objects, but, if that is impossible - I wonder for any other method to do that.

Any help is very much appreciate.

not sure, why do you need special classes for tests. Can't you use those already existing ones? — Sergio Tulentsev, Sep 06 '16 at 14:22
Those new derived classes, when hardcoded in app - have to connect to real external services. Here I want to test some usage, without connecting to external world. — Dimitri, Sep 06 '16 at 14:54
I found that code here: http://stackoverflow.com/questions/5302187/ruby-string-to-class-name — Dimitri, Sep 06 '16 at 14:58
you could stub code that calls external world. `allow(gate).to receive(:fetch_commission_or_whatever).and_return(0.05)` — Sergio Tulentsev, Sep 06 '16 at 15:05
Also you could use VCR to record and replay responses from external services. — Sergio Tulentsev, Sep 06 '16 at 15:06

score 0 · Accepted Answer · answered Sep 06 '16 at 15:59

Ok, I spend about two hours before posting the question, but I found answer only after posting =)

I had just to move the class definition inside attribute's one.

FactoryGirl.define do
  factory :gate do

    name { FFaker::Company.name }
    type { 
      class_name = 'Gate' + name.gsub( /[[:blank:][:cntrl:][:punct:]]/,'' ).to_s.singularize
      gate_class = class_name.classify
      class_instance  = Class.new(Gate) do
        def comission_in(amount)
          amount * 0.01 + 5
        end
        def comission_out(amount)
          amount * 0.02 + 5
        end
      end
      Object.const_set( gate_class, class_instance )
      puts " gate_class: '#{ gate_class }'; name: '#{ name }';"
      class_name
    }
    country { FFaker::Address.country_code }

  end
end

Creating some class during tests (STI)

1 Answers1