呼び出し側で属性指定
呼び出し時にハッシュを渡すとデフォルトの値を上書きしてデータを生成できる
spec/factories/users.rb
FactoryGirl.define do
factory :user do
name "Isaac Newton"
role "physicist"
gender "male"
end
end
user = FactoryGirl.create(:user, name: "Max Planck")
user.name
# "Max Planck"
user.role
# "physicist"
user.gender
# "male"
ネストによるfactoryの継承（inheritance）
factoryをネストすると親の属性をすべて引き継いだ上で、子のfactoryで指定した属性を上書きしたデータを生成できる.
spec/factories/users.rb
FactoryGirl.define do
factory :user do
name "Isaac Newton"
role "physicist"
gender "male"
factory :mathematician do
role "mathematician"
end
factory :woman do
gender "female"
end
end
end
user = FactoryGirl.create(:user)
user.name
# "Isaac Newton"
user.role
# "physicist"
user.gender
# "male"
mathematician = FactoryGirl.create(:mathematician)
mathematician.name
# "Isaac Newton"
mathematician.role
# "mathematician"
mathematician.gender
# "male"
woman = FactoryGirl.create(:woman)
woman.name
# "Isaac Newton"
woman.role
# "physicist"
woman.gender
# "female"
parentによるfactoryの継承（inheritance）
ネストによるfactoryの継承はparent属性を使って以下のように書くこともできる.
spec/factories/users.rb
FactoryGirl.define do
factory :user do
name "Isaac Newton"
role "physicist"
gender "male"
end
factory :mathematician, parent: :user do
role "mathematician"
end
factory :woman, parent: :user do
gender "female"
end
end
user = FactoryGirl.create(:user)
user.name
# "Isaac Newton"
user.role
# "physicist"
user.gender
# "male"
mathematician = FactoryGirl.create(:mathematician)
mathematician.name
# "Isaac Newton"
mathematician.role
# "mathematician"
mathematician.gender
# "male"
woman = FactoryGirl.create(:woman)
woman.name
# "Isaac Newton"
woman.role
# "physicist"
woman.gender
# "female"
trait
継承はデータセットのファクトリ名のラベル(:userなど)が新たに作成されるのに対して、traitでは呼び出し側でtrait名を指定する. より柔軟にパターンを網羅させることができる.
spec/factories/users.rb
FactoryGirl.define do
factory :user do
name "Isaac Newton"
role "physicist"
gender "male"
trait :mathematician do
role "mathematician"
end
trait :professor do
role "professor"
end
trait :father do
role "father"
gender "male"
end
trait :mother do
role "mother"
gender "female"
end
trait :man do
gender "male"
end
trait :woman do
gender "female"
end
end
end
呼び出し時に第２引数にtrait名を指定するとそのtraitブロックで属性を上書きしたデータが返る.
FactoryGirl.create(:user, :mathematician).role
# "mathematician"
mother = FactoryGirl.create(:user, :mother)
mother.name
# "Isaac Newton"
mother.role
# "mother"
mother.gender
# "female"
traitは複数指定でき、後に指定したtraitが前の属性を上書きする
user = FactoryGirl.create(:user, :father, :woman)
user.name
# "Isaac Newton"
user.role
# "father"
user.gender
# "female"
traitを組み合わせたfactoryを作成
factory定義時にtraits属性で配列を渡せばtraitを組み合わせたfactoryを作成できる.
spec/factories/users.rb
FactoryGirl.define do
factory :user do
name "Isaac Newton"
role "physicist"
gender "male"
trait :mathematician do
role "mathematician"
end
trait :professor do
role "professor"
end
trait :man do
gender "male"
end
trait :woman do
gender "female"
end
end
factory :newton_mathematician, traits: [:mathematician], parent: :user
factory :newton_professor, traits: [:professor], parent: :user
factory :newton_woman_professor, traits: [:professor, :woman], parent: :user
end
user = FactoryGirl.create(:newton_mathematician)
user.name
# "Isaac Newton"
user.role
# "mathematician"
user.gender
# "male"
user = FactoryGirl.create(:newton_woman_professor)
user.name
# "Isaac Newton"
user.role
# "professor"
user.gender
# "female"
Conclusion
各属性のパターンはtraitで用意しそれらを組み合わせて、かつ継承を利用して基本的なデータパターンを網羅し、レアケースや汎用性のないデータは呼び出し側で用意する、といった使い方が有効そう.
なるべくテスト計画上重要なパターンをtraitで作成したい.
References
Environment
% ruby -v
ruby 2.1.1p76 (2014-02-24 revision 45161) [x86_64-linux]
% gem list factory_girl
*** LOCAL GEMS ***
factory_girl (4.4.0)
factory_girl_rails (4.4.1)