Rails教程:RSpec测试解耦

Question

我正在尝试在Michael Hartl的Ruby on Rails教程中进行第8.5章练习2.演习如下:

按照第8.3.3节中的示例,浏览用户和身份验证请求规范(即当前在spec/requests目录中的文件),并在spec/support/utilities.rb中定义实用程序函数,以将测试与实现分离.额外的功劳:将支持代码组织到单独的文件和模块中,并通过在spec帮助文件中正确包含模块来使一切工作正常.

例8.3.3:utilities.rb

include ApplicationHelper

def valid_signin(user)
  fill_in "Email",    with: user.email
  fill_in "Password", with: user.password
  click_button "Sign in"
end

RSpec::Matchers.define :have_error_message do |message|
  match do |page|
    page.should have_selector('div.alert.alert-error', text: message)
  end
end

已定义的valid_signin(user)函数用于以下块中authentication_pages_spec.rb并且工作正常.

describe "with valid information" do
    let(:user){FactoryGirl.create(:user)}
    before { valid_signin(user) }

    it { should have_selector('title', text: user.name) }
    it { should have_link('Profile', href: user_path(user)) }
    it { should have_link('Sign out', href: signout_path) }
    it { should_not have_link('Sign in', href: signin_path) }

    describe "followed by signout" do
        before { click_link "Sign out" }
        it { should have_link('Sign in') }
    end
end

所以在这个例子中,我开始创建自己的名字valid_signup(user):

def valid_signup(user)
    fill_in "Name",         with: user.name
    fill_in "Email",        with: user.email
    fill_in "Password",     with: user.password
    fill_in "Confirmation",         with: user.password_confirmation
end

我正在使用这个块user_pages_spec.rb:

describe "with valid information" do
  let(:user){FactoryGirl.create(:user)}
  before { valid_signup(user) }

  it "should create a user" do
    expect { click_button submit }.to change(User, :count).by(1)
  end

  describe "after saving the user" do
    before { click_button submit }
    let(:user) { User.find_by_email(user.email) }

    it { should have_selector('title', text: user.name) }
    it { should have_selector('div.alert.alert-success', text: 'Welcome') }
    it { should have_link('Sign out') }
  end
end

它不起作用.Spork/Guard报告这些错误:

Failures:

  1) UserPages signup with valid information should create a user
     Failure/Error: expect { click_button submit }.to change(User, :count).by(1)
       count should have been changed by 1, but was changed by 0
     # ./spec/requests/user_pages_spec.rb:46:in `block (4 levels) in '

  2) UserPages signup with valid information after saving the user 
     Failure/Error: before { valid_signup(user) }
     NoMethodError:
       undefined method `name' for nil:NilClass
     # ./spec/support/utilities.rb:10:in `valid_signup'
     # ./spec/requests/user_pages_spec.rb:43:in `block (4 levels) in '

  3) UserPages signup with valid information after saving the user 
     Failure/Error: before { valid_signup(user) }
     NoMethodError:
       undefined method `name' for nil:NilClass
     # ./spec/support/utilities.rb:10:in `valid_signup'
     # ./spec/requests/user_pages_spec.rb:43:in `block (4 levels) in '

  4) UserPages signup with valid information after saving the user 
     Failure/Error: before { valid_signup(user) }
     NoMethodError:
       undefined method `name' for nil:NilClass
     # ./spec/support/utilities.rb:10:in `valid_signup'
     # ./spec/requests/user_pages_spec.rb:43:in `block (4 levels) in '

错误似乎表明我的valid_signup(user)函数中的user.name utilities.rb没有定义,但我没有看到任何理由.我已经多次重启Guard了,并rake db:test:prepare确保测试db(使用postgresql)是有序的.

这是我factories.rb的完整性:

FactoryGirl.define do
    factory :user do
        name    "Example User"
        email   "user@example.com"
        password    "foobar"
        password_confirmation   "foobar"
    end
end

在我继续尝试解耦更多测试套件之前,我非常希望解决此错误,更重要的是,了解它的原因.

编辑

我已经尝试了你的提示,并按user_pages_spec.rb如下方式编辑了该功能:

describe "with valid information" do
      before { valid_signup(user) }

      it "should create a user" do
        expect { click_button submit }.to change(User, :count).by(1)
      end

      describe "after saving the user" do
        before { click_button submit }
        let(:user) { User.find_by_email('user@example.com') }

        it { should have_selector('title', text: user.name) }
        it { should have_selector('div.alert.alert-success', text: 'Welcome') }
        it { should have_link('Sign out') }
      end
    end

由于我let(:user){FactoryGirl.create(:user)}从函数中删除了我猜测在函数中不再创建用户所以我需要定义valid_signup(user)为user变量for valid_signup不再由FactoryGirl填充:

def valid_signup(user)
    fill_in "Name",     with: "Example User"
    fill_in "Email",    with: "user@example.com"
    fill_in "Password", with: "foobar"
    fill_in "Confirmation", with: "foobar"
end

这没用,给了我以下错误:

Failures:


1) UserPages signup with valid information should create a user
     Failure/Error: before { valid_signup(user) }
     NameError:
       undefined local variable or method user' for #<RSpec::Core::ExampleGroup::Nested_5::Nested_3::Nested_2:0x007fdafc5088c0>
     # ./spec/requests/user_pages_spec.rb:42:inblock (4 levels) in '

2) UserPages signup with valid information after saving the user 
     Failure/Error: it { should have_selector('title', text: user.name) }
     NoMethodError:
       undefined method name' for nil:NilClass
     # ./spec/requests/user_pages_spec.rb:52:inblock (5 levels) in '

我也尝试过valid_signup(user)以前用过它的方式运行测试(user.name, user.email, user.password, user.password_confirmation有的,也没用,有错误:

Failures:

  1) UserPages signup with valid information should create a user
     Failure/Error: before { valid_signup(user) }
     NameError:
       undefined local variable or method `user' for #
     # ./spec/requests/user_pages_spec.rb:42:in `block (4 levels) in '

  2) UserPages signup with valid information after saving the user 
     Failure/Error: it { should have_selector('title', text: user.name) }
     NoMethodError:
       undefined method `name' for nil:NilClass
     # ./spec/requests/user_pages_spec.rb:52:in `block (5 levels) in '

接下来我尝试运行它而不传递变量user_pages_spec.rb:before { valid_signup() }并且函数中没有变量utilities.rb:

def valid_signup()
    fill_in "Name",     with: "Example User"
    fill_in "Email",    with: "user@example.com"
    fill_in "Password", with: "foobar"
    fill_in "Confirmation", with: "foobar"
end

这返回:

Failures:

  1) UserPages signup with valid information should create a user
     Failure/Error: before { valid_signup(user) }
     NameError:
       undefined local variable or method `user' for #
     # ./spec/requests/user_pages_spec.rb:42:in `block (4 levels) in '

  2) UserPages signup with valid information after saving the user 
     Failure/Error: it { should have_selector('title', text: user.name) }
     NoMethodError:
       undefined method `name' for nil:NilClass
     # ./spec/requests/user_pages_spec.rb:52:in `block (5 levels) in '

仍然没有接近答案.我可能会忽略一些简单的事情.不知道是什么.我得到了我第一次做错的事情:我只是认为FactoryGirl是一种创建变量的方法,我不知道它实际上对我的测试数据库做了些什么.

Answer 1

我将尝试解释您的原始测试中发生的情况（我发现它比编辑后的版本更容易修复）：

describe "with valid information" do
  let(:user) {FactoryGirl.build(:user)} # FactoryGirl.create will save the instance, you should be using build instead
  before { valid_signup(user) }

  it "should create a user" do
    expect { click_button submit }.to change(User, :count).by(1)
  end

  describe "after saving the user" do
    before { click_button submit }
    # let(:user) { User.find_by_email(user.email) } # this is not needed any more 

    it { should have_selector('title', text: user.name) }
    it { should have_selector('div.alert.alert-success', text: 'Welcome') }
    it { should have_link('Sign out') }
  end
end

有关 FactoryGirl 使用的更多信息：https://github.com/thoughtbot/factory_girl/blob/master/GETTING_STARTED.md#using-factories