it 'returns the options field when empty' do
      valid_asset = FactoryGirl.create(:asset)
      asset_mappings = [
        {
          isbn_canonical: valid_asset.isbn_canonical,
          partner_id: partner_id,
          options: {}
        }
      ]

      binding.pry
      post(:create, params: { feature_id: feature.id, asset_mappings: asset_mappings, format: :json })

      response.status.must_equal(200)

      asset_feature = json['asset_features'].first
      asset_feature['id'].wont_be_nil
      asset_feature['feature_id'].must_equal(feature.id)
      asset_feature['asset_id'].must_equal(valid_asset.id)
      asset_feature['partner_id'].must_equal(partner_id)
      asset_feature['options'].must_equal(JSON.parse('{}'))
    end