Rspec，在Rails应用程序控制器中存根对象的存在

Question

I have a method 'get_location_details' in my application controller which is called after the venue is found, before every action. It looks like this,

  def get_venue 
    @venue = Venue.friendly.find(params[:venue_id])
  end 

  def get_location_details
    @venue_information = {
    opening_times: @venue.facility_with_opening_hours.any? ? venue.facility_with_opening_hours.first.opening_times_for_week(Date.today) : '',
    location:   {address1:   venue.address1, 
                 address2:   venue.address2, 
                 town:       venue.town, 
                 county:     venue.county, 
                 postcode:   venue.postcode},
    contact:    {email:      venue.email, 
                 telephone:  venue.telephone},
    social:     {facebook:   venue.facebook,
                 twitter:    venue.twitter}    
    }
  end

I want to begin testing i. the output, ii. context's (ie. where a venue isn't present). I assume that in order to achieve this i need to stub the presence of the venue, which is what I cant seem to figure out how to do.

  describe "get_location_details" do 
    before do 
      test_hash = [{:day=>"Mon - Fri", :open=>"2001-01-01 06:30:00 +0000", :close=>"2001-01-01 22:00:00 +0000", :closed=>false},
                  {:day=>"Sat", :open=>"2001-01-01 08:00:00 +0000", :close=>"2001-01-01 19:00:00 +0000", :closed=>false},
                  {:day=>"Sun", :open=>"2001-01-01 08:00:00 +0000", :close=>"2001-01-01 17:00:00 +0000", :closed=>false}]
      allow(controller).to receive(:venue).and_return(venue)
      allow(venue).to receive(:facility_with_opening_hours).and_return(test_hash)
    end

    it "returns http success" do
      expect(controller.send(:get_location_details).is_a?(Hash)).to be_truthy
    end

  end 

However my test keeps failing with

   undefined method `facility_with_opening_hours' for nil:NilClass

which indicates the venue isn't being stubbed. How can i stub the venue? What am I doing wrong here? I often trip up on application controller testing, but I want to get to grips with it. If anyone can recommend any further reading that would be greatly appreciated.

Many Thanks

Answer 1

I'm not sure you can easily stub a member in rspec. You can either set the member with a value, or (preferably) refactor your code to read the value from a getter rather than a member:

def venue 
  @venue ||= Venue.friendly.find(params[:venue_id])
end 

def location_details
  @venue_information ||= {
    opening_times: venue.facility_with_opening_hours.any? ? venue.facility_with_opening_hours.first.opening_times_for_week(Date.today) : '',
    location:   {address1:   venue.address1, 
    address2:   venue.address2, 
    town:       venue.town, 
    county:     venue.county, 
    postcode:   venue.postcode},
    contact:    {email:      venue.email, 
             telephone:  venue.telephone},
    social:     {facebook:   venue.facebook,
             twitter:    venue.twitter}    
  }
end