Split method into higher-level smaller methods

app/services/cap_quantity_and_store_changes.rb

@@ -3,34 +3,42 @@
 class CapQuantityAndStoreChanges
   def initialize(order)
     @order = order
+    @changes = {}
   end
 
   def call
-    changes = {}
+    cap_insufficient_stock!
+    verify_line_items
 
-    order.insufficient_stock_lines.each do |line_item|
-      changes[line_item.id] = line_item.quantity
-      line_item.cap_quantity_at_stock!
-    end
-
-    unavailable_stock_lines_for.each do |line_item|
-      changes[line_item.id] = changes[line_item.id] || line_item.quantity
-      line_item.update(quantity: 0)
-
-      Spree::OrderInventory.new(order).verify(line_item, order.shipment)
-    end
-
-    if changes.present?
-      order.line_items.reload
-      order.update_order_fees!
-    end
+    reload_order if changes.present?
 
     changes
   end
 
   private
 
-  attr_reader :order
+  attr_reader :order, :changes
+
+  def cap_insufficient_stock!
+    order.insufficient_stock_lines.each do |line_item|
+      changes[line_item.id] = line_item.quantity
+      line_item.cap_quantity_at_stock!
+    end
+  end
+
+  def verify_line_items
+    unavailable_stock_lines_for.each do |line_item|
+      changes[line_item.id] = changes[line_item.id] || line_item.quantity
+      line_item.update(quantity: 0)
+
+      Spree::OrderInventory.new(order).verify(line_item, order.shipment)
+    end
+  end
+
+  def reload_order
+    order.line_items.reload
+    order.update_order_fees!
+  end
 
   def unavailable_stock_lines_for
     order.line_items.where('variant_id NOT IN (?)', available_variants_for.select(&:id))