Add specs for error cases in shipments_controller_spec

spec/controllers/spree/api/shipments_controller_spec.rb

@@ -17,11 +17,12 @@ describe Spree::Api::ShipmentsController, type: :controller do
     let!(:variant) { create(:variant) }
     let(:params) do
       { quantity: 2,
-        variant_id: stock_location.stock_items.first.variant.to_param,
+        variant_id: variant.to_param,
         order_id: order.number,
         stock_location_id: stock_location.to_param,
         format: :json }
     end
+    let(:error_message) { "broken shipments creation" }
 
     before do
       order.update_attribute(:ship_address_id, order_ship_address.id)
@@ -63,6 +64,14 @@ describe Spree::Api::ShipmentsController, type: :controller do
         expect(json_response["inventory_units"].size).to eq 2
         expect(order.reload.line_items.first.price).to eq(variant_override.price)
       end
+
+      it 'returns error code when adding to order contents fails' do
+        make_order_contents_fail
+
+        spree_post :create, params
+
+        expect_error_response
+      end
     end
 
     context 'for a completed order with shipment' do
@@ -70,38 +79,60 @@ describe Spree::Api::ShipmentsController, type: :controller do
 
       before { params[:id] = order.shipments.first.to_param }
 
-      it 'adds a variant to the shipment' do
-        spree_put :add, params
+      context '#add' do
+        it 'adds a variant to the shipment' do
+          spree_put :add, params
 
-        expect_valid_response
-        expect(inventory_units_for(json_response["inventory_units"], variant).size).to eq 2
+          expect_valid_response
+          expect(inventory_units_for(json_response["inventory_units"], variant).size).to eq 2
+        end
+
+        it 'returns error code when adding to order contents fails' do
+          make_order_contents_fail
+
+          spree_put :add, params
+
+          expect_error_response
+        end
+
+        it 'adds a variant override to the shipment' do
+          hub = create(:distributor_enterprise)
+          order.update_attribute(:distributor, hub)
+          variant_override = create(:variant_override, hub: hub, variant: variant)
+
+          spree_put :add, params
+
+          expect_valid_response
+          expect(inventory_units_for(json_response["inventory_units"], variant).size).to eq 2
+          expect(order.reload.line_items.last.price).to eq(variant_override.price)
+        end
       end
 
-      it 'removes a variant from the shipment' do
-        params[:variant_id] = order.line_items.first.variant.to_param
-        params[:quantity] = 1
+      context '#remove' do
+        before do
+          params[:variant_id] = order.line_items.first.variant.to_param
+          params[:quantity] = 1
+        end
 
-        spree_put :remove, params
+        it 'removes a variant from the shipment' do
+          spree_put :remove, params
 
-        expect_valid_response
-        expect(inventory_units_for(json_response["inventory_units"], variant).size).to eq 0
+          expect_valid_response
+          expect(inventory_units_for(json_response["inventory_units"], variant).size).to eq 0
+        end
+
+        it 'returns error code when removing from order contents fails' do
+          make_order_contents_fail
+
+          spree_put :remove, params
+
+          expect_error_response
+        end
       end
+    end
 
-      it 'adds a variant override to the shipment' do
-        hub = create(:distributor_enterprise)
-        order.update_attribute(:distributor, hub)
-        variant_override = create(:variant_override, hub: hub, variant: variant)
-
-        spree_put :add, params
-
-        expect_valid_response
-        expect(inventory_units_for(json_response["inventory_units"], variant).size).to eq 2
-        expect(order.reload.line_items.last.price).to eq(variant_override.price)
-      end
-
-      def inventory_units_for(inventory_units, variant)
-        inventory_units.select { |unit| unit['variant_id'] == variant.id }
-      end
+    def inventory_units_for(inventory_units, variant)
+      inventory_units.select { |unit| unit['variant_id'] == variant.id }
     end
 
     def expect_valid_response
@@ -109,5 +140,15 @@ describe Spree::Api::ShipmentsController, type: :controller do
       attributes.all?{ |attr| json_response.key? attr.to_s }
       expect(json_response["shipping_method"]["name"]).to eq order.shipping_method.name
     end
+
+    def make_order_contents_fail
+      expect(Spree::Order).to receive(:find_by_number!) { order }
+      expect(order).to receive(:contents) { raise error_message }
+    end
+
+    def expect_error_response
+      expect(response.status).to eq 422
+      expect(json_response["exception"]).to eq error_message
+    end
   end
 end