ruby-on-rails - 无方法错误 : undefined method `RuntimeError'

Question

我在 Ruby 库中编写了一些代码(顺便在 Rails 中使用)，引发了如下所示的 RuntimeError:

class MyClass
  def initialize(opts = {})
     # do stuff
     thing = opts[:thing]
     raise RuntimeError "must have a thing!" unless thing.present? && thing.is_a?(Thing)
     # more stuff
  end
end

当我在上面运行我的新 rspec 规范时，它看起来有点像:

it "should raise an error if we don't pass a thing" do
  lambda {
    my_class = MyClass.new(:thing => nil)
  }.should raise_exception(RuntimeError)
end

我不断得到一些奇怪的东西:

expected RuntimeError, got 
#<NoMethodError: undefined method `RuntimeError' for #<MyClass:0xb5acbf9c>>

Answer 1

您可能已经发现了问题...啊，单字符错误，doncha love em？

在这里。

错误:

 raise RuntimeError "must have a thing!" unless thing.present? && thing.is_a?(Thing)

右:

 raise RuntimeError, "must have a thing!" unless thing.present? && thing.is_a?(Thing)

当然，您也可以直接忽略 RuntimeError:

 raise "must have a thing!" unless thing.present? && thing.is_a?(Thing)

因为无论如何它都是默认的...