ruby-on-rails – 使用Shoulda对Rails模型重构rspec测试

通过回答 another StackOverflow question on attribute accessibility tests(并认为它们相当棒极了),在学习了 shoulda-matchers后,我决定尝试重构 The Rails Tutorial中的模型测试,以使它们更加简洁和彻底.我这样做是因为模块 Shoulda::Matchers::ActiveRecord和 Shoulda::Matchers::ActiveModel的文档以及 this StackOverflow answer在模型中进行测试的一些灵感.但是,还有一些我不太清楚的事情,我想知道这些测试如何能够更好地进行.

我将使用Rails教程中的用户规范作为我的例子,因为它是最详细的,并且涵盖了许多可以改进的领域.以下代码示例已从原来的user_spec.rb更改,并将代码替换为描述“微孔关联”行.针对user.rb型号的规格测试,其工厂定义在factories.rb.

规格/型号/ user_spec.rb

# == Schema Information
#
# Table name: users
#
#  id              :integer          not null,primary key
#  name            :string(255)
#  email           :string(255)
#  created_at      :datetime         not null
#  updated_at      :datetime         not null
#  password_digest :string(255)
#  remember_token  :string(255)
#  admin           :boolean          default(FALSE)
#
# Indexes
#
#  index_users_on_email           (email) UNIQUE
#  index_users_on_remember_token  (remember_token)
#

require 'spec_helper'

describe User do

  let(:user) { FactoryGirl.create(:user) }

  subject { user }

  describe "database schema" do
    it { should have_db_column(:id).of_type(:integer)
                              .with_options(null: false) }
    it { should have_db_column(:name).of_type(:string) }
    it { should have_db_column(:email).of_type(:string) }
    it { should have_db_column(:created_at).of_type(:datetime)
                              .with_options(null: false) }
    it { should have_db_column(:updated_at).of_type(:datetime)
                              .with_options(null: false) }
    it { should have_db_column(:password_digest).of_type(:string) }
    it { should have_db_column(:remember_token).of_type(:string) }
    it { should have_db_column(:admin).of_type(:boolean)
                              .with_options(default: false) }
    it { should have_db_index(:email).unique(true) }
    it { should have_db_index(:remember_token) }
  end

  describe "associations" do
    it { should have_many(:microposts).dependent(:destroy) }
    it { should have_many(:relationships).dependent(:destroy) }
    it { should have_many(:followed_users).through(:relationships) }
    it { should have_many(:reverse_relationships).class_name("Relationship")
                         .dependent(:destroy) }
    it { should have_many(:followers).through(:reverse_relationships) }
  end

  describe "model attributes" do
    it { should respond_to(:name) }
    it { should respond_to(:email) }
    it { should respond_to(:password_digest) }
    it { should respond_to(:remember_token) }
    it { should respond_to(:admin) }
    it { should respond_to(:microposts) }
    it { should respond_to(:relationships) }
    it { should respond_to(:followed_users) }
    it { should respond_to(:reverse_relationships) }
    it { should respond_to(:followers) }
  end

  describe "virtual attributes and methods from has_secure_password" do
    it { should respond_to(:password) }
    it { should respond_to(:password_confirmation) }
    it { should respond_to(:authenticate) }
  end

  describe "accessible attributes" do
    it { should_not allow_mass_assignment_of(:password_digest) }
    it { should_not allow_mass_assignment_of(:remember_token) }
    it { should_not allow_mass_assignment_of(:admin) }
  end

  describe "instance methods" do
    it { should respond_to(:feed) }
    it { should respond_to(:following?) }
    it { should respond_to(:follow!) }
    it { should respond_to(:unfollow!) }
  end

  describe "initial state" do
    it { should be_valid }
    it { should_not be_admin }
    its(:remember_token) { should_not be_blank }
    its(:email) { should_not =~ /p{Upper}/ }
  end

  describe "validations" do
    context "for name" do
      it { should validate_presence_of(:name) }
      it { should_not allow_value(" ").for(:name) }
      it { should ensure_length_of(:name).is_at_most(50) }
    end

    context "for email" do
      it { should validate_presence_of(:email) }
      it { should_not allow_value(" ").for(:email) }
      it { should validate_uniqueness_of(:email).case_insensitive }

      context "when email format is invalid" do
        addresses = %w[user@foo,com user_at_foo.org example.user@foo.]
        addresses.each do |invalid_address|
          it { should_not allow_value(invalid_address).for(:email) }
        end
      end

      context "when email format is valid" do
        addresses = %w[user@foo.COM A_US-ER@f.b.org frst.lst@foo.jp a+b@baz.cn]
        addresses.each do |valid_address|
          it { should allow_value(valid_address).for(:email) }
        end
      end
    end

    context "for password" do
      it { should ensure_length_of(:password).is_at_least(6) }
      it { should_not allow_value(" ").for(:password) }

      context "when password doesn't match confirmation" do
        it { should_not allow_value("mismatch").for(:password) }
      end
    end

    context "for password_confirmation" do
      it { should validate_presence_of(:password_confirmation) }
    end
  end

  # ...
end

关于这些测试的一些具体问题：

>是否值得测试数据库模式？ StackOverflow answer mentioned above中的评论说：“我只测试与行为相关的事情,我不认为存在列或索引行为.除非有人故意删除它们,否则数据库列不会消失,而是可以防止与代码审查和信任“,我同意,但有什么有效的原因为什么数据库模式的结构将被测试,从而证明存在的Shoulda :: Matchers :: ActiveRecord模块？也许只是重要的指标值得测试？
>应该在“关联”下应该有__any测试替换它们相应的应该在“模型属性”下进行测试？我不知道应该有__any测试只是在模型文件中查找相关的has_many声明,或者实际上执行与respond_to相同的功能.
>您有任何其他意见/建议,使这些测试更简洁/可读/彻底,内容和结构？

def matches?(subject)
  @subject = subject
  association_exists? &&
    macro_correct? &&
    foreign_key_exists? &&
    through_association_valid? &&
    dependent_correct? &&
    class_name_correct? &&
    order_correct? &&
    conditions_correct? &&
    join_table_exists? &&
    validate_correct?
end