has_many 的 TDD 通过 RSpec 和 RSpec 进行模型验证工厂女孩

Question

请考虑以下事项：

ScheduledSession ------> Applicant <------ ApplicantSignup

注意事项：

1. ScheduledSession 将始终存在于系统中；将其视为一门课程或课程。
2. 这里的目的是在 signups_controller#create 期间根据 ScheduledSession 上的属性验证 ApplicantSignup 模型

Associations

class ScheduledSession < ActiveRecord::Base
  has_many :applicants, :dependent => :destroy
  has_many :applicant_signups, :through => :applicants
  #...
end

class ApplicantSignup < ActiveRecord::Base
  has_many :applicants, :dependent => :destroy
  has_many :scheduled_sessions, :through => :applicants
  #...
end

class Applicant < ActiveRecord::Base
  belongs_to :scheduled_session
  belongs_to :applicant_signup

  # TODO: enforce validations for presence
  # and uniqueness constraints etc.
  #...
end

SignupsController

资源是 RESTful，即 #create 操作将具有类似于 /scheduled_sessions/:id/signups/new 的路径，

def new
  @session = ScheduledSession.find(params[:scheduled_session_id])
  @signup = @session.signups.new
end

def create
  @session = ScheduledSession.find(params[:scheduled_session_id])
  @session.duration = (@session.end.to_time - @session.start.to_time).to_i
  @signup = ApplicantSignup.new(params[:signup].merge(:sessions => [@session]))

  if @signup.save
   # ...
  else
    render :new
  end
end

您会注意到我在上面设置了一个虚拟属性@session.duration 以防止 Session 被视为无效。真正的“魔法”发生在 @signup = ApplicantSignup.new(params[:signup].merge(:sessions => [@session])) 中，这意味着在模型中我可以从 self.scheduled_sessions 中进行选择并访问此 ApplicantSignup 正在构建的 ScheduledSession，即使在此时，没有任何记录存在在连接表中。

例如，模型验证看起来像

def ensure_session_is_upcoming
  errors[:base] << "Cannot signup for an expired session" unless self.scheduled_sessions.select { |r| r.upcoming? }.size > 0
end

def ensure_published_session
  errors[:base] << "Cannot signup for an unpublished session" if self.scheduled_sessions.any? { |r| r.published == false }
end

def validate_allowed_age
  # raise StandardError, self.scheduled_sessions.inspect
  if self.scheduled_sessions.select { |r| r.allowed_age == "adults" }.size > 0
    errors.add(:dob_year) unless (dob_year.to_i >= Time.now.strftime('%Y').to_i-85 && dob_year.to_i <= Time.now.strftime('%Y').to_i-18)
    # elsif ... == "children"
  end
end  

上面的内容在开发中运行得很好，并且验证按预期工作 - 但如何使用 Factory Girl 进行测试呢？我希望单元测试能够保证我已经实现的业务逻辑——当然，这是事后发生的，但仍然是 TDD 的一种方式。

您会注意到我在上面的最后一次验证中注释掉了 raise StandardError, self.scheduled_sessions.inspect — 这将为 self.scheduled_sessions 返回 [] 这表明我的工厂设置不正确。

众多尝试之一=)

it "should be able to signup to a session" do
  scheduled_session = Factory.build(:scheduled_session)
  applicant_signup = Factory.build(:applicant_signup)
  applicant = Factory.create(:applicant, :scheduled_session => scheduled_session, :applicant_signup => applicant_signup)
  applicant_signup.should be_valid
end

it "should be able to signup to a session for adults if between 18 and 85 years" do
  scheduled_session = Factory.build(:scheduled_session)
  applicant_signup = Factory.build(:applicant_signup)
  applicant_signup.dob_year = 1983 # 28-years old
  applicant = Factory.create(:applicant, :scheduled_session => scheduled_session, :applicant_signup => applicant_signup)
  applicant_signup.should have(0).error_on(:dob_year)
end

第一个通过了，但老实说我不相信它正确验证了applicant_signup模型； self.scheduled_sessions 返回 [] 的事实仅仅意味着上面的内容是不正确的。

我很可能正在尝试测试 Factory Girl 范围之外的东西，或者是否有更好的方法来解决这个问题？感谢所有评论、建议和建设性批评！

更新：

• 不确定这叫什么，但这是至少针对 如何在控制器级别实现
• 我需要考虑至少在关联方面忽略 Factory Girl 并尝试通过模拟返回 scheduled_session applicant_signup 模型上的 scheduled_sessions。

工厂

FactoryGirl.define do  
  factory :signup do
    title "Mr."
    first_name "Franklin"
    middle_name "Delano"
    last_name "Roosevelt"
    sequence(:civil_id) {"#{'%012d' %  Random.new.rand((10 ** 11)...(10 ** 12))}"}    
    sequence(:email) {|n| "person#{n}@#{(1..100).to_a.sample}example.com" }
    gender "male"
    dob_year "1980"
    sequence(:phone_number) { |n| "#{'%08d' %  Random.new.rand((10 ** 7)...(10 ** 8))}" }
    address_line1 "some road"
    address_line2 "near a pile of sand"
    occupation "code ninja"
    work_place "Dharma Initiative"
  end

  factory :session do
    title "Example title"
    start DateTime.civil_from_format(:local,2011,12,27,16,0,0)
    duration 90
    language "Arabic"
    slides_language "Arabic & English"
    venue "Main Room"
    audience "Diabetic Adults"
    allowed_age "adults"
    allowed_gender "both"
    capacity 15
    published true
    after_build do |session|
      # signups will be assigned manually on a per test basis
      # session.signups << FactoryGirl.build(:signup, :session => session)
    end  
  end

  factory :applicant do
    association :session
    association :signup
  end

  #...
end 

Answer 1

我之前的假设是正确的，只是做了一些小改动：

我需要考虑忽略 Factory Girl 的关联方面
至少并尝试通过存根返回scheduled_session
application_signup 模型上的 Scheduled_sessions。

让我的测试变得非常简单：

it "should be able to applicant_signup to a scheduled_session" do
  scheduled_session = Factory(:scheduled_session)
  applicant_signup = Factory.build(:applicant_signup)
  applicant_signup.stub!(:scheduled_sessions).and_return{[scheduled_session]}
  applicant_signup.should be_valid
end

it "should be able to applicant_signup to a scheduled_session for adults if between 18 and 85 years" do
  scheduled_session = Factory(:scheduled_session)
  applicant_signup = Factory.build(:applicant_signup)
  applicant_signup.dob_year = 1983 # 28-years old
  applicant_signup.stub!(:scheduled_sessions).and_return{[scheduled_session]}
  applicant_signup.should have(0).error_on(:dob_year)
  applicant_signup.should be_valid
end

这个测试特别需要类似的方法：

it "should not be able to applicant_signup if the scheduled_session capacity has been met" do
  scheduled_session = Factory.build(:scheduled_session, :capacity => 3)
  scheduled_session.stub_chain(:applicant_signups, :count).and_return(3)    
  applicant_signup = Factory.build(:applicant_signup)
  applicant_signup.stub!(:scheduled_sessions).and_return{[scheduled_session]}
  applicant_signup.should_not be_valid
end

...并且成功 - 忽略测试持续时间，因为 spork 会导致错误报告。

Finished in 2253.64 seconds
32 examples, 0 failures, 3 pending
Done.

Answer 2

作为另一种方法，您可以使用 Rspecs stub_model。

另外，如果您测试 ApplicantSignup，则应该对其进行初始化，而不是测试 Applicant 的创建。例如：

applicant_signup = Factory.build(:applicant_signup);

applicant_signup.should_receive(:scheduled_sessions)
                           .and_return{[scheduled_sessi‌​on]};

因此数据库访问会减少，您将测试ApplicantSignup，而不是Applicant。