Notify when stock limit reached on cart rather than silently capping

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

@@ -30,7 +30,7 @@
     -#   "price-breakdown-placement" => "left",
     -#   "price-breakdown-animation" => true}
   %td.text-center.cart-item-quantity{"data-hook" => "cart_item_quantity"}
-    = item_form.number_field :quantity, :min => 0, :max => variant.on_hand, :class => "line_item_quantity", :size => 5
+    = item_form.number_field :quantity, :min => 0, "ofn-on-hand" => variant.on_hand, :class => "line_item_quantity", :size => 5
   %td.cart-item-total.text-right{"data-hook" => "cart_item_total"}
     = line_item.display_amount_with_adjustments.to_html unless line_item.quantity.nil?
 

spec/features/consumer/shopping/cart_spec.rb

@@ -32,12 +32,20 @@ feature "full-page cart", js: true do
     describe "updating quantities with insufficient stock available" do
       let(:li) { order.line_items(true).last }
 
-      use_short_wait 10
-
       before do
         variant.update_attributes! on_hand: 2
       end
 
+      it "prevents me from entering an invalid value" do
+        visit spree.cart_path
+
+        accept_alert 'Insufficient stock available, only 2 remaining' do
+          fill_in "order_line_items_attributes_0_quantity", with: '4'
+        end
+
+        page.should have_field "order_line_items_attributes_0_quantity", with: '2'
+      end
+
       it "shows the quantities saved, not those submitted" do
         fill_in "order_line_items_attributes_0_quantity", with: '4'