关于使用 rspec 测试模型的建议

Question

我刚刚开始使用 rspec，我想听听您对此规范的看法。 我有 2 个模型

class City < ActiveRecord::Base
  validates :name, :presence => true, :uniqueness => true
  validates :department_id, :presence => true
  belongs_to :department
end

，

class Department < ActiveRecord::Base
  validates :name, :presence => true, :uniqueness => true
  has_many :cities
end

我写下了这些规格，以满足验证和关系声明：

city_spec.rb

describe City do

  before(:each) do
    @city = Factory(:city)
  end

  describe "validation" do
    it "valid" do
      @city.should be_valid
      @city.should have(:no).errors_on(:name)
      @city.should have(:no).errors_on(:department_id)
    end

    it "has a unique name" do
      c = Factory.build(:city, :name => @city.name)
      c.should_not be_valid
      c.name = 'unique'
      c.should be_valid
      # or via shoulda
      c.should validate_uniqueness_of(:name)
    end

    it "belongs to department" do
      c = Factory.build(:city, :department_id => nil)
      c.should have(1).error_on(:department_id)
      c.department_id = @city.department_id
      c.should be_valid
      c.should belong_to(:department)
    end
  end
end

Department_spec.rb

describe Department do

  before(:each) do
    @department = Factory(:department)
  end

  describe "validation" do
   it "has a name" do
    d = Factory.build(:department, :name => nil)
    d.should_not be_valid
    d.should have(1).error_on(:name)
    d.name = 'good name'
    d.should be_valid
  end

  it "has a unique name" do
    d = Factory.build(:department, :name => @department.name)
    d.should_not be_valid
    d.name = 'good name'
    d.should be_valid
  end

  it "has many cities" do
    d = Factory.build(:department)
    c1 = Factory.build(:city)
    c2 = Factory.build(:city)
    d.cities << c1
    d.cities << c2
    d.cities.size.should == 2
    d.cities.first.should == c1
    d.cities.last.should == c2
    # or via shoulda
    d.should have_many(:cities)
 end
 end
 end

你可以看到我也使用了 shoulda gem，你认为这种做法正确吗？我为这个功能写了太多测试？ 谢谢

Answer 1

乍一看，您似乎专注于测试模型对象的状态。那完全没问题。我唯一要考虑的是这些模型是否有任何相关的行为？它们是否包含任何实现业务逻辑的方法？如果没有，我相信你就可以回家了。如果你这样做，那么我会为这些行为添加测试。

Answer 2

我绝对建议使用 shoulda 来测试你的模型：

当使用 rspec 时，你应该在 gem 文件的测试组中使用 shoulda-matchers gem：

gem 'shoulda-matchers', :require => false

在你的 spec_helper.rb 中添加 require 'shoulda-matchers' 之后需要“rspec/rails”。

然后，您只需使用以下测试：

city_spec.rb

it { should validate_prescence_of(:name) }
it { should validate_prescence_of(:department_id) }
it { should belong_to(:department) }

对于唯一性测试，您需要在测试之前创建一个 city 实例，但随后您将使用：

it { should validate_uniqueness_of(:name) }

正如您所看到的 - 比您编写的测试更干净、更清晰。