如何使用 rspec 指定 draper 装饰器。

Question

我正在尝试为我的装饰器中的各个功能编写规范。我的助手有如下规格（这只是一个示例）：

book_helper.rb

module BookHelper
  def heading_title
    @book.name[0..200]
  end
end

book_helper_spec.rb

require 'spec_helper'

describe BookHelper do
  subject { FactoryGirl.build(:book) }

  it 'limits title to 200 characters' do
    title = 'Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Aenean commodo ligula eget dolor. Aenean massa. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Donec quam felis, ultricies nec, pellentesque eu, pretium.'
    subject.name = title
    subject.save
    @book = subject
    expect(heading_title).to eq(title[0..200])
  end
end

给定以下装饰器，我该如何为函数编写规范？

book_decorator.rb

class BookDecorator < Draper::Decorator
  delegate_all

  def display_days
    model.months_to_display * 30
  end
end

Answer 1

对于您的示例，我会尝试类似：

require 'spec_helper'

describe BookDecorator do
  let(:book) { FactoryGirl.build_stubbed(:book).decorate }

  it 'returns the displayed days' do
    expect(book.display_days).to eq('600')
  end

end

Answer 2

只需对生成的实体使用 .decorate（使用 FactoryGirl 或 Faker）