Save shipping category selection to new variant when creating a new product

app/models/spree/product.rb

@@ -69,7 +69,8 @@ module Spree
 
     # Transient attributes used temporarily when creating a new product,
     # these values are persisted on the product's variant
-    attr_accessor :price, :display_as, :unit_value, :unit_description, :tax_category_id
+    attr_accessor :price, :display_as, :unit_value, :unit_description, :tax_category_id,
+                  :shipping_category_id
 
     after_create :ensure_standard_variant
     after_save :update_units
@@ -290,6 +291,7 @@ module Spree
       variant.unit_value = unit_value
       variant.unit_description = unit_description
       variant.tax_category_id = tax_category_id
+      variant.shipping_category_id = shipping_category_id
       variants << variant
     end
 

spec/models/spree/product_spec.rb

@@ -207,6 +207,7 @@ module Spree
 
         context "saving a new product" do
           let!(:product){ Spree::Product.new }
+          let!(:shipping_category){ create(:shipping_category) }
 
           before do
             create(:stock_location)
@@ -217,7 +218,7 @@ module Spree
             product.variant_unit_scale = 1000
             product.unit_value = 1
             product.price = 4.27
-            product.shipping_category = create(:shipping_category)
+            product.shipping_category_id = shipping_category.id
             product.save!
           end
 
@@ -225,6 +226,7 @@ module Spree
             expect(product.variants.reload.length).to eq 1
             standard_variant = product.variants.reload.first
             expect(standard_variant.price).to eq 4.27
+            expect(standard_variant.shipping_category).to eq shipping_category
           end
         end