Sort line items by name and unit_value for confirmation email and summary screen

app/models/spree/line_item_decorator.rb

@@ -32,6 +32,13 @@ Spree::LineItem.class_eval do
     end
   }
 
+  scope :sorted_by_name_and_unit_value,     
+      # Find line items that are from order sorted by variant name and unit value
+      joins(:variant=> :product).
+        reorder('spree_products.name asc, spree_variants.unit_value asc').
+        select('spree_line_items.*')
+  
+
   scope :supplied_by, lambda { |enterprise|
     joins(:product).
       where('spree_products.supplier_id = ?', enterprise)

app/views/spree/order_mailer/_order_summary.html.haml

@@ -11,7 +11,7 @@
         %h4
           = t :email_order_summary_price
   %tbody
-    - @order.line_items.each do |item|
+    - @order.line_items.sorted_by_name_and_unit_value.each do |item|
       %tr
         %td
           = render 'spree/shared/line_item_name', line_item: item

app/views/spree/orders/_summary.html.haml

@@ -11,7 +11,7 @@
       %th.text-right.total
         %span= t(:total)
   %tbody{"data-hook" => ""}
-    - order.line_items.each do |item|
+    - order.line_items.sorted_by_name_and_unit_value.each do |item|
       %tr.line_item{"data-hook" => "order_details_line_item_row", class: "variant-#{item.variant.id}" }
         %td(data-hook = "order_item_description")
 

spec/models/spree/line_item_spec.rb

@@ -14,6 +14,18 @@ module Spree
       let(:li1) { create(:line_item, order: o, product: p1) }
       let(:li2) { create(:line_item, order: o, product: p2) }
 
+      
+      let(:p3) {create(:product, name: 'Clear Honey') }
+      let(:p4) {create(:product, name: 'Apricots') }
+      let(:v1) {create(:variant, product: p3, unit_value: 500) }
+      let(:v2) {create(:variant, product: p3, unit_value: 250) }
+      let(:v3) {create(:variant, product: p4, unit_value: 500) }
+      let(:v4) {create(:variant, product: p4, unit_value: 1000) }
+      let(:li3) { create(:line_item, order: o, product: p3, variant: v1) }
+      let(:li4) { create(:line_item, order: o, product: p3, variant: v2) }
+      let(:li5) { create(:line_item, order: o, product: p4, variant: v3) }
+      let(:li6) { create(:line_item, order: o, product: p4, variant: v4) }
+
       it "finds line items for products supplied by a particular enterprise" do
         LineItem.supplied_by(s1).should == [li1]
         LineItem.supplied_by(s2).should == [li2]
@@ -40,6 +52,10 @@ module Spree
           LineItem.without_tax.should == [li2]
         end
       end
+
+      it "finds line items sorted by name and unit_value" do
+        o.line_items.sorted_by_name_and_unit_value.should == [li5,li6,li4,li3]
+      end
     end
 
     describe "capping quantity at stock level" do