Henry's Blog

RSpec Tutorials Models Test

上一篇博客介绍了测试的相关概念，软件开发过程中，要对测试有足够的重视。 而且对于 Ruby 开发的项目，测试更是极其重要。
下面，将总结一下在 Rails 项目中如何引入 RSpec，并对代码进行充分的测试。

RSpec 介绍

    RSpec is testing tool for the Ruby programming language.
    Born under the banner of Behaviour-Driven Development, it is designed to
    make Test-Driven Development a productive and enjoyable experience.

    However we use FactoryGirl to set up Ruby objects as test data.
    It support for multiple build strategies (saved instances, unsaved instances,
    attribute hashes, and stubbed objects), and support for multiple factories for
    the same class (user, admin_user, and so on), including factory inheritance.

    If we want to use factory_girl with Rails, we need to include factory_girl_rails.
我们将结合 FactoryGirl 以及 factory_girl，来取代 Test::Unit 和 Fixture。

开发记录

1. 新建一个项目 rspec_tutorials.
项目源代码 Github 地址：rspec_tutorials
2. 在 Gemfile 中引入一下gems

    group :test, :development do
      gem "rspec-rails"
      gem "factory_girl"
      gem "factory_girl_rails"
    end
3. 安装 RSpec
执行以下两个命令 
    bundle install
    rails generate rspec:install
以上命令将安装 RSpec 依赖的gems，并且在项目下创建 spec 目录以及创建 spec_helper.rb 文件。

4. 创建模型
创建一个 User 模型，包含姓名:name, 年龄:age, 性别:gender。 
    rails g model user name:string age:integer gender:string
5. 准备数据库
在 development 数据库中，创建 users 表；将 development 数据库表结构 clone 至 test 数据库。 
    rake db:create
    rake db:migrate
6. 编写 User 模型相关代码
    # app/models/user.rb

    class User < ActiveRecord::Base
      extend Enumerize

      enumerize :gender, in: [:male, :female]

      attr_accessible :age, :name, :gender

      def youngster?
        self.age.present? && self.age < 18
      end

    end
7. 编写 User 模型 factories 数据示例
    # spec/factories/users.rb

    FactoryGirl.define do
      factory :man, :class => 'User' do
        name "Henry"
        age 25
        gender 'male'
      end

      factory :woman, :class => 'User' do
        name "Alice"
        age 12
        gender 'female'
      end
    end
8. 编写 User 模型 RSpec 测试代码
    # spec/models/user_spec.rb

    require 'spec_helper'

    describe User do
      let(:man) { FactoryGirl.create(:man) }
      let(:woman) { FactoryGirl.create(:woman) }

      describe "man" do
        it "should be male" do
          man.gender.male?.should be_true
        end

        it "should not be a youngster" do
          man.youngster?.should be_false
        end
      end

      describe "woman" do
        it "should be female" do
          woman.gender.female?.should be_true
        end

        it "should be a youngster" do
          woman.youngster?.should be_true
        end
      end
    end
9. 命令行运行测试
    1. run all tests
      rake spec

    2. run all modles tests
      rake spec:models

    3. run single test file
      rspec spec/models/user_spec.rb

    4. run single test method within a test file
      rspec file_path:line_no

      The line_no is the method location in your test file. Such as:

      rspec spec/models/user_spec.rb:10
10. 测试执行结果
    $ rake spec
    /Users/leehenry/.rvm/rubies/ruby-1.9.3-p125/bin/ruby -S rspec ./spec/models/user_spec.rb
    ....

    Finished in 0.04613 seconds
    4 examples, 0 failures

    Randomized with seed 33203

2013-06-12

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