如何将i18n_scope存根在Rails 4 rspec 3.3.0上模拟ActiveRecord :: RecordInvalid？

Question

我试过这段代码,但它引发了错误: NameError: uninitialized constant RSpec::Mocks::Mock

RSpec::Mocks::Mock.stub(:i18n_scope).and_return(:activerecord)
model = double(:model, errors: double(:errors, full_messages: []))
ActiveRecord::RecordInvalid.new(model)

我怎么能存根i18n_scope？

Answer 1

要回答你的问题,你必须存根,RSpec::Mocks::Double因为那是你实际传递给ActiveRecord :: RecordInvalid的实例的类.但是,这不起作用,因为RSpec::Mocks::Double没有实现.i18n_scope.所以,我所做的(我讨厌它)是RSpec::Mocks::Double使用虚拟方法修补类.

  it "does something cool" do
    foo = MyClass.new
    class RSpec::Mocks::Double
      def self.i18n_scope
        :activerecord
      end
    end
    error_double = double(:model, errors: double(:errors,full_messages: ["blah"]))
    expect(foo).to receive(:bar).and_raise(ActiveRecord::RecordInvalid, error_double)
    ...
  end

但是通过利用块参数,有一种更好的方法:

  it "does something cool" do
    foo = MyClass.new
    expect(foo).to receive(:bar) do |instance|
      instance.errors.add(:base, "invalid error")
      raise(ActiveRecord::RecordInvalid, instance)
    end
    ...
  end

通过这种方式,您可以更接近应用程序数据/逻辑与黑客RSpec进行测试.

这对于控制器测试非常有效,我正在从#update抛出的特定错误中解救!在某些情况下的方法.