Draper - NoMethodError 与 RSpec 测试装饰器

Question

我在尝试使用 Draper 进行测试时收到以下错误：

NoMethodError: undefined method 'with_unit' for nil:NilClass

这是我的测试代码：

# spec/decorators/food_decorator_spec.rb
require 'spec_helper'

describe FoodDecorator do
  before { ApplicationController.new.set_current_view_context }
  FactoryGirl.create(:food)
  @food = FoodDecorator.first

  specify { @food.with_unit('water').should == "85.56 g" }
end

这是我的装饰器代码：

class FoodDecorator < ApplicationDecorator
  decorates :food

  def with_unit(nutrient)
    model.send(nutrient.to_sym).to_s + " g"
  end
end

我的研究表明，ApplicationController.new.set_current_view_context 行应该可以解决此问题，但事实并非如此。有什么想法吗？

Answer 1

替换为：

require 'spec_helper'

describe FoodDecorator do
  before do
    ApplicationController.new.set_current_view_context
    FactoryGirl.create(:food)
    @food = FoodDecorator.first
  end

  specify { @food.with_unit('water').should == "85.56 g" }
end

你甚至可以这样做：

require 'spec_helper'

describe FoodDecorator do

  let(:food) { Factory(:food) }
  subject { FoodDecorator.first }

  before do
    food
    ApplicationController.new.set_current_view_context
  end

  specify { subject.with_unit('water').should == "85.56 g" }
end