Ruby on Rails Michael Hartl 第 8.5 章测试失败

Question

我已经看到这个问题再次被问到，其中 current_user 变量被定义了两次。我的代码中有同样的错误，但是删除 current_user 的第二个定义仍然不能解决我收到的错误消息。这是我在运行测试时收到的错误消息：

---

  1) Failure:
SessionsHelperTest#test_current_user_returns_right_user_when_session_is_nil [/home/ubuntu/workspace/sample_app/test/helpers/sessions_helper_test.rb:11]:
--- expected
+++ actual
@@ -1 +1 @@
-#<User id: 762146111, name: "Michael Example", email: "michael@example.com", created_at: "2016-06-06 19:15:21", updated_at: "2016-06-06 19:15:21", password_digest: "$2a$04$LkmHj4hHVcRoTuEH6icLs.E/GebaKaY2Y/TX5nqouIj...", remember_digest: nil>
+nil

---

这是我的 session_helper 文件：

---

module SessionsHelper
  #logs in the given user
  def log_in(user)
    session[:user_id] = user.id
  end

  #remembers a user in a persistent session
  def remember(user)
    user.remember
    cookies.permanent.signed[:user_id] = user.id
    cookies.permanent[:remember_token] = user.remember_token
  end

  #returns current logged in user
  #def current_user
    #@current_user ||= User.find_by(id: session[:user_id])
  #end

  #returns the user corresponding to the remember token
  def current_user
    if (user_id = session[:user_id])
      @current_user ||= User.find_by(id: user_id)
    elsif (user_id = cookies.signed[:user_id])
      user = User.find_by(id: user_id)
      if user && user.authenticated?(cookies[:remember_token])
        log_in user
        @current_user = user
      end
    end
  end

  def logged_in?
    !current_user.nil?
  end

  def log_out
    session.delete(:user_id)
    @current_user = nil
  end

  #forgets a persistent session
  def forget(user)
    user.forget
    cookies.delete(:user_id)
    cookies.delete(:remember_token)
  end

  #logs out the current user
  def log_out
    forget(current_user)
    session.delete(:user_id)
    @current_user = nil
  end
end   

---

这是我的 users_login_test 文件：

---

require 'test_helper'

class UsersLoginTest < ActionDispatch::IntegrationTest

  def setup
    @user = users(:michael)
  end

  test "Login with invalid information followed by logout" do
    get login_path
    post login_path, session: { email: @user.email, password: 'password' }
    assert is_logged_in?
    assert_redirected_to @user
    follow_redirect!
    assert_template 'users/show'
    assert_select "a[href=?]", login_path, count: 0
    assert_select "a[href=?]", logout_path
    assert_select "a[href=?]", user_path(@user)
    delete logout_path
    assert_not is_logged_in?
    assert_redirected_to root_url
    #simulate a user logging out in a different window
    delete logout_path
    follow_redirect!
    assert_select "a[href=?]", login_path
    assert_select "a[href=?]", logout_path,      count: 0
    assert_select "a[href=?]", user_path(@user), count: 0
  end

  test "login with remembering" do
    log_in_as(@user, remember_me: '1')
    assert_not_nil cookies['remember_token']
  end

  test "login without remembering" do
    log_in_as(@user, remember_me: '0')
    assert_nil cookies['remember_token']
  end
end

---

这是我的 test_helper 文件：

---

ENV['RAILS_ENV'] ||= 'test'
require File.expand_path('../../config/environment', __FILE__)
require 'rails/test_help'

class ActiveSupport::TestCase
  fixtures :all

  # Returns true if a test user is logged in.
  def is_logged_in?
    !session[:user_id].nil?
  end

  # Logs in a test user.
  def log_in_as(user, options = {})
    password    = options[:password]    || 'password'
    remember_me = options[:remember_me] || '1'
    if integration_test?
      post login_path, session: { email:       user.email,
                                  password:    password,
                                  remember_me: remember_me }
    else
      session[:user_id] = user.id
    end
  end

  private

    # Returns true inside an integration test.
    def integration_test?
      defined?(post_via_redirect)
    end
end

---

这是我的 users.yml 文件：

---

michael:
  name: Michael Example
  email: michael@example.com
  password_digest: <%= User.digest('password') %>

---

我真的不确定出了什么问题，但我想我只是错过了一些东西。任何帮助将非常感激！谢谢！

---

编辑：这是我的 user.rb 文件：

---

class User < ActiveRecord::Base
  attr_accessor :remember_token
  before_save { self.email = email.downcase }
  validates :name,  presence: true, length: { maximum: 50 }
  VALID_EMAIL_REGEX = /\A[\w+\-.]+@[a-z\d\-.]+\.[a-z]+\z/i
  validates :email, presence: true, length: { maximum: 255 },
                    format: { with: VALID_EMAIL_REGEX },
                    niqueness: { case_sensitive: false }
  has_secure_password
  validates :password, presence: true, length: { minimum: 6 }

  #returns the digest of a given string
  def User.digest(string)
    cost = ActiveModel::SecurePassword.min_cost ?     BCrypt::Engine::MIN_COST :
                                              BCrypt::Engine.cost
    BCrypt::Password.create(string, cost: cost)
  end

  #returns random token
  def User.new_token
    SecureRandom.urlsafe_base64
  end

  #remembers a user in the database for persistent sessions
  def remember
    self.remember_token = User.new_token
    update_attribute(:remember_token, User.digest(remember_token))
  end

  #returms true if the given token matches the digest
  def authenticated?(remember_token)
    return false if remember_digest.nil?
    BCrypt::Password.new(remember_digest).is_password?    (remember_token)
  end

  #Forgets a user
  def forget
    update_attribute(:remember_digest, nil)
  end

end

---

编辑：sessions_helper_test.rb：

---

require 'test_helper'

class SessionsHelperTest < ActionView::TestCase

  def setup
    @user = users(:michael)
    remember(@user)
  end

  test "current_user returns right user when session is nil" do
    assert_equal @user, current_user
    assert is_logged_in?
  end

  test "current_user returns nil when remember digest is wrong" do
    @user.update_attribute(:remember_digest, User.digest(User.new_token))
    assert_nil current_user
  end
end

Answer 1

查看您的 session_helper.rb，# Logs out the current user 方法已在文件中定义了两次。根据第 8 章中的本教程，为了运行绿色测试套件，您需要在文件中包含以下内容。

我认为您在 清单 8.39 中搞砸了，您只需要在 log_out 方法中添加一行。

请在 sessions_helper.rb 中填写以下代码，您的测试将变为绿色。

module SessionsHelper

  # Logs in the given user.
  def log_in(user)
    session[:user_id] = user.id
  end

  # Remembers a user in a persistent session.
  def remember(user)
    user.remember
    cookies.permanent.signed[:user_id] = user.id
    cookies.permanent[:remember_token] = user.remember_token
  end

  # Returns the user corresponding to the remember token cookie.
  def current_user
    if (user_id = session[:user_id])
      @current_user ||= User.find_by(id: user_id)
    elsif (user_id = cookies.signed[:user_id])
      user = User.find_by(id: user_id)
      if user && user.authenticated?(cookies[:remember_token])
        log_in user
        @current_user = user
      end
    end
  end

  # Returns true if the user is logged in, false otherwise.
  def logged_in?
    !current_user.nil?
  end
# Forgets a persistent session.
  def forget(user)
    user.forget
    cookies.delete(:user_id)
    cookies.delete(:remember_token)
  end

  # Logs out the current user.
  def log_out
    forget(current_user)
    session.delete(:user_id)
    @current_user = nil
  end
end

更新： 同样根据清单 8.45 在 app/models/user.rb 文件中，您需要添加一行 return false if remember_digest.nil?。所以 user.rb 文件应该如下。

class User < ActiveRecord::Base
  attr_accessor :remember_token
  before_save { self.email = email.downcase }
  validates :name,  presence: true, length: { maximum: 50 }
  VALID_EMAIL_REGEX = /\A[\w+\-.]+@[a-z\d\-.]+\.[a-z]+\z/i
  validates :email, presence: true, length: { maximum: 255 },
                    format: { with: VALID_EMAIL_REGEX },
                    uniqueness: { case_sensitive: false }
  has_secure_password
  validates :password, presence: true, length: { minimum: 6 }

  # Returns the hash digest of the given string.
  def User.digest(string)
    cost = ActiveModel::SecurePassword.min_cost ? BCrypt::Engine::MIN_COST :
                                                  BCrypt::Engine.cost
    BCrypt::Password.create(string, cost: cost)
  end

  # Returns a random token.
  def User.new_token
    SecureRandom.urlsafe_base64
  end

  # Remembers a user in the database for use in persistent sessions.
  def remember
    self.remember_token = User.new_token
    update_attribute(:remember_digest, User.digest(remember_token))
  end

  # Returns true if the given token matches the digest.
  def authenticated?(remember_token)
    return false if remember_digest.nil? #Add this line
    BCrypt::Password.new(remember_digest).is_password?(remember_token)
  end

  # Forgets a user.
  def forget
    update_attribute(:remember_digest, nil)
  end
end

如果您进一步遇到任何错误，请告诉我。