RSPEC 测试子类 STI 方法轨道 4.

Question

我正在尝试为 sti 子类上的方法构建一个 rspec 测试，该测试只读取父模型的方法。 该方法在应用程序中有效，只是在 rspec 测试中不起作用。 我不知道我错过了什么

模型/动物

/动物.rb

class Animal < ActiveRecord::Base
  def favorite
    "unicorn"
  end
end

模型/动物/mammal_animal.rb

class MammalAnimal < Animal
  def favorite
    "whale"
  end
end

模型/动物/cat_mammal_animal.rb

class CatMammalAnimal < MammalAnimal
  def favorite
    "tabby"
  end
end

mammal_animal_spec.rb

require 'rails_helper'
RSpec.describe MammalAnimal, type: :model do
  let(:cat_mammal_animal) {FactoryGirl.create(:cat_factory)}
  subject(:model) { cat_mammal_animal }
  let(:described_class){"MammalAnimal"}
  describe "a Cat" do
    it "should initialize successfully as an instance of the described class" do
      expect(subject).to be_a_kind_of described_class
    end
    it "should have attribute type" do
      expect(subject).to have_attribute :type
    end
    it "has a valid factory" do 
      expect(cat_mammal_animal).to be_valid
    end
    describe ".favorite " do 
      it 'shows the favorite Cat' do
        expect(cat_mammal_animal.type).to eq("CatMammalAnimal")
        expect(cat_mammal_animal.favorite).to include("tabby")
        expect(cat_mammal_animal.favorite).not_to include("whale")
        expect(cat_mammal_animal.favorite).not_to include("unicorn")
        print cat_mammal_animal.favorite
      end
    end
  end
end

错误

Failures:
  1) MammalAnimal.favorite and .favorite shows the favorite Cat
     Failure/Error: expect(cat_mammal_animal.type).to include("tabby")
       expected "unicorn" to include "tabby"
     # ./spec/models/mammal_animal_spec.rb:82:in `block (3 levels) in <top (required)>'

更新

动物.rb

FactoryGirl.define do
  factory :animal do
    type 'Animal'
    name "dragon"

    trait :mammal do
      type 'MammalAnimal'
      name "zebra"
    end
    trait :cat do
      type 'CatMammalAnimal'
      name "calico"
    end
    factory :mammal_factory, traits: [:mammal]
    factory :cat_factory, traits: [:cat]
  end
end

根据建议，我将以下行添加到测试中

expect（cat_mammal_animal.class.constantize）.to eq（CatMammalAnimal）

并得到此错误

1）哺乳动物动物最爱和最爱显示最喜欢的猫 失败/错误： 期望（cat_animal_mammal.class.constantize）.to eq（CatMammalAnimal）

 NoMethodError:
   undefined method `constantize' for #<Class:0x007f8ed4b8b0e0>
   Did you mean?  constants

Answer 1

我认为与其使用 trait 来创建子类的对象，不如为这些对象设置单独的工厂。

factory :animal do
  name 'dragon'
end
factory :mammal, class: MammalAnimal do
  name 'zebra'
end
factory :cat, class: CatMammalAnimal do
  name 'calico'
end

所有这些都可以在animals.rb中定义

然后，您可以创建诸如

create(:animal)
create(:mammal)
create(:cat)