Adding optional manual override of line item stock level check

app/models/spree/line_item_decorator.rb

@@ -7,8 +7,12 @@ Spree::LineItem.class_eval do
   # Redefining here to add the inverse_of option
   belongs_to :order, :class_name => "Spree::Order", inverse_of: :line_items
 
+  # Allows manual skipping of stock_availability check
+  attr_accessor :skip_stock_check
+
   attr_accessible :max_quantity, :final_weight_volume, :price
   attr_accessible :final_weight_volume, :price, :as => :api
+  attr_accessible :skip_stock_check
 
   before_save :calculate_final_weight_volume, if: :quantity_changed?, unless: :final_weight_volume_changed?
   after_save :update_units
@@ -139,6 +143,13 @@ Spree::LineItem.class_eval do
 
   private
 
+  # Override of Spree validation method
+  # Added check for in-memory :skip_stock_check attribute
+  def stock_availability
+    return if skip_stock_check || sufficient_stock?
+    errors.add(:quantity, I18n.t('validation.exceeds_available_stock'))
+  end
+
   def scoper
 	  return @scoper unless @scoper.nil?
 	  @scoper = OpenFoodNetwork::ScopeVariantToHub.new(order.distributor)

spec/models/spree/line_item_spec.rb

@@ -535,5 +535,24 @@ module Spree
         }.to change(Spree::OptionValue, :count).by(0)
       end
     end
+
+    describe "checking stock availability" do
+      let(:line_item) { LineItem.new }
+
+      context "when skip_stock_check is not set" do
+        it "checks stock" do
+          expect(line_item).to receive(:sufficient_stock?) { true }
+          line_item.send(:stock_availability)
+        end
+      end
+
+      context "when skip_stock_check is set to true" do
+        before { line_item.skip_stock_check = true }
+        it "does not check stock" do
+          expect(line_item).to_not receive(:sufficient_stock?)
+          line_item.send(:stock_availability)
+        end
+      end
+    end
   end
 end