Rspec integral factories in test - ruby

Question

I apologize if my English is not perfect but it is not my native language.
I have to test a MySql database with Rails 4.2, Rspec 3.3 and FactoryGirl 4.5.
The tests of base models are green. The problems comes when I have to test a model that contains foreign keys that can't be duplicated.
At first I have two models (dimension.rb through feature.rb and technical.rb) each having a foreign key that comes from the same model (current.rb):
#models/dimension.rb
class Dimension < ActiveRecord::Base
belongs_to :current
has_many :features
...
end
#models/feature.rb
class Feature < ActiveRecord::Base
belongs_to :dimension
has_many :bxes
...
end
#models/technical.rb
class Technical < ActiveRecord::Base
belongs_to :current
has_many :bxes
...
end
These two models are placed in the final model (bxe.rb)
#models/bxe.rb
class Bxe < ActiveRecord::Base
belongs_to :feature
belongs_to :technical
...
validates :technical_id, presence: true
validates :feature_id, presence: true
end
The Current model is:
#models/current.rb
class Current < ActiveRecord::Base
has_many :technicals
has_many :dimensions
validates :current, presence: true, uniqueness: true
validates :value, presence: true, uniqueness: true
end
The factories are the following:
#spec/factories/current.rb
FactoryGirl.define do
factory :current do
trait :lower do
current '800A'
value 800
end
trait :higher do
current '2000A'
value 2000
end
end
end
#spec/factories/dimension.rb
FactoryGirl.define do
factory :dimension do
...
trait :one do
current {create(:current, :lower)}
end
trait :two do
current {create(:current, :higher)}
end
end
end
#spec/factories/feature.rb
FactoryGirl.define do
factory :feature do
descr 'MyString'
dimension { create(:dimension, :one) }
...
end
end
#spec/factories/technical.rb
FactoryGirl.define do
factory :technical do
...
trait :A do
current { create(:current, :lower) }
end
trait :L do
current { create(:current, :higher) }
end
end
end
#spec/factories/bxes.rb
FactoryGirl.define do
factory :bxe do
...
technical {create(:technical, :A) }
feature
end
end
When I run the test on the models the first command (technical) runs and the factory creates a Current record with id = 1 but the second (features) fails, since the factory try again to create the record of Current with the same data, action prohibited from the model current.rb
#rspec spec/models
2.1.2 :001 > FactoryGirl.create(:bxebusbar, :one)
... Current Exists ... SELECT 1 AS one FROM `currents` WHERE `currents`.`current` = BINARY '800A' LIMIT 1
... INSERT INTO `currents` (`current`, `value`, `created_at`, `updated_at`) VALUES ('800A', 800, ..., ...)
... INSERT INTO `technicals` (..., `current_id`, ..., `created_at`, `updated_at`) VALUES (..., 1, ..., ...)
... Current Exists ... SELECT 1 AS one FROM `currents` WHERE `currents`.`current` = BINARY '800A' LIMIT 1
... ActiveRecord::RecordInvalid: Validation failed: Current has already been taken, Value has already been taken
I think that the problem can be solved by creating once only Current record and then using it in the technical and features factories, what would happen in reality, but I do not know how to do that.
Any suggestion? Thanks

Answer 1

You can use sequences to generate values that will not be duplicated. Another option is to use DatabaseCleaner and setup it to clean database after each test.
With first option:
FactoryGirl.define do
factory :current do
trait :lower do
sequence :current do { |n| "#{n}A" }
sequence :value do {|n| "#{n}" }
end
end
end
Or to setup DataBase Cleaner: Database cleaner