如何在should上下文中重写设置值，如RSpec“let”

Question

这是我在RSpec中使用的一种很好的技术，我也想在使用Shoulda和Shoulda上下文的项目中使用它。但我不知道这是否可能。有办法做到这一点吗？

我想要的是：在引用嵌套上下文中的let子句的外部上下文中定义setup（before）块。这样，内部上下文可以配置在外部setup中引用的值，并且setup在内部上下文中仍然可以是DRY。

RSpec示例（这个示例很简单——请假设我的真实示例在before块中有更多我不想重复的代码）：

describe Thing do
  before do
    # Notice that `user` isn't defined here--it's defined in `let` blocks
    # in nested contexts below.
    login_as user
    # Assume there's lots more code here that I would like to keep
    # DRY across contexts.
  end
  context "when logged in as an admin" do
    # THIS IS THE MAGIC RIGHT HERE:
    let(:user) { Factory(:user, role: "admin") }
    it "should ..." ...
  end
  context "when logged in as a normal user" do
    # THIS IS THE MAGIC RIGHT HERE:
    let(:user) { Factory(:user) }
    it "should ..." ...
  end
end

总结一下：我如何使用should上下文和Test:：Unit来做到这一点？

我已经尝试过一些没有效果的东西：

• def在每个子文本中重新定义一个方法
• CCD_ 8

Answer 1

我发现测试类中的辅助方法对于提取测试之间重复的代码非常有用。像这样：

class MyTest < TestCase
  context "when logged in as an admin" do
    setup do
      do_login Factory(:user, role: "admin")
    end
    should "..." do
      ...@user...
    end
  end
  context "when logged in as an admin" do
    setup do
      do_login Factory(:user)
    end
    should "..." do
      ...@user...
    end
  end
  def do_login(user)
    login_as user
    @user = user
    # lots more setup code here...
  end
end