The Kai Way

[译文] Shoulda教程3 - Model Helpers

ActiveRecord助手方法 #

Shoulda具有一套ActiveRecord测试宏，这让开发效率大大提高，TDD变得轻而易举。关于这个方面的所有的文档都在Shoulda的Rdoc中。下面就来个小小的例子：

    class UserTest
      should_has_many  :dogs
      should_belong_to :lover
    end

上面的代码创建了如下的测试：

test: Person should allow phone_number to be set to "(123) 456-7890".
test: Person should belong to lover.
test: Person should have many dogs.
test: Person should have many messes through dogs.
test: Person should have one profile.
test: Person should not allow admin to be changed by update.
test: Person should not allow phone_number to be set to "1234".
test: Person should not allow phone_number to be set to "abcd".
test: Person should require name to be set.
test: Person should require phone_number to be set.
test: Person should require unique value for name.

前提 #

一件需要知道的事情是一些ActiveRecord测试宏找到第一个初始的记录(通过 Class.find(:first))。你可以让这个工作通过一个具有一条记录的fixture文件，或者通过在setup中创建一条记录，类似下面这样：

    class UserTest < Test::Unit::TestCase
      def setup
        @user = User.create!(params)
      end

      should_require_unique_attributes :name
    end

或者通过一个context，如下：

    class UserTest < Test::Unit::TestCase
      context "given an existing record" do
        setup do
          @user = User.create!(params)
        end

        should_require_unique_attributes :name
      end
    end

但是Shoulda不止是提供了对模型的测试，还提供了很多强大的助手方法可以使用于控制器。