make all business decisions directly visible in the act method

Author: porbas

ecommerce/processes/lib/processes/reservation_process.rb

@@ -39,7 +39,13 @@ def apply(event)
     def act
       case state
       in order: :accepted
-        update_order_state { reserve_stock }
+        begin
+          reserve_stock
+        rescue SomeInventoryNotAvailable => exc
+          reject_order(exc.unavailable_products)
+        else
+          accept_order
+        end
       in order: :cancelled
         release_stock(state.reserved_product_ids)
       in order: :confirmed
@@ -66,13 +72,6 @@ def reserve_stock
       end
     end
 
-    def update_order_state
-      yield
-      accept_order
-    rescue SomeInventoryNotAvailable => exc
-      reject_order(exc.unavailable_products)
-    end
-
     def release_stock(product_ids)
       state.order_lines.slice(*product_ids).each do |product_id, quantity|
         command_bus.(Inventory::Release.new(product_id: product_id, quantity: quantity))