Fixing up a bug in the aggregate filtering

lib/open_food_network/products_and_inventory_report.rb

@@ -42,7 +42,9 @@ module OpenFoodNetwork
     end
 
     def filter(variants)
-      filter_on_hand filter_to_supplier filter_to_distributor filter_to_order_cycle variants
+      # NOTE: Ordering matters.
+      # filter_to_order_cycle and filter_to_distributor return Arrays not Arel
+      filter_to_distributor filter_to_order_cycle filter_on_hand filter_to_supplier variants
     end
 
     def filter_on_hand(variants)

spec/lib/open_food_network/products_and_inventory_report_spec.rb

@@ -130,6 +130,20 @@ module OpenFoodNetwork
           subject.stub(:params).and_return(order_cycle_id: order_cycle.id)
           subject.filter(variants).should == [product1.master]
         end
+
+        it "should do all the filters at once" do
+          distributor = create(:distributor_enterprise)
+          product1 = create(:simple_product, supplier: supplier, distributors: [distributor])
+          product2 = create(:simple_product, supplier: supplier, distributors: [distributor])
+          order_cycle = create(:simple_order_cycle, suppliers: [supplier], distributors: [distributor], variants: [product1.master])
+
+          subject.stub(:params).and_return(
+            order_cycle_id: order_cycle.id,
+            supplier_id: supplier.id,
+            distributor_id: distributor.id,
+            report_type: 'inventory')
+          subject.filter(variants)
+        end
       end
     end
   end