Refactor to simplify outgoing_exchange_variant_ids

lib/open_food_network/order_cycle_form_applicator.rb

@@ -157,7 +157,7 @@ module OpenFoodNetwork
         variants[variant_id.to_i] = value  if permitted.include?(variant_id.to_i)
       end
 
-      variants.select { |k, v| v }.keys.map { |k| k.to_i }.sort
+      variants_to_a variants
     end
 
     def outgoing_exchange_variant_ids(attrs)
@@ -167,27 +167,36 @@ module OpenFoodNetwork
       sender = @order_cycle.coordinator
       receiver = exchange.andand.receiver || Enterprise.find(attrs[:enterprise_id])
       permitted = editable_variant_ids_for_outgoing_exchange_between(sender, receiver)
-      incoming = incoming_variant_ids
 
       # Only change visibility for variants I have permission to edit
       attrs[:variants].each do |variant_id, value|
         variant_id = variant_id.to_i
 
-        if !incoming.include? variant_id
-          # When a variant has been removed from incoming but remains
-          # in outgoing, remove it from outgoing too
-          variants[variant_id] = false
-
-        elsif permitted.include? variant_id
-          variants[variant_id] = value
-        end
+        variants = update_outgoing_variants(variants, permitted, variant_id, value)
       end
 
-      variants.select { |k, v| v }.keys.map(&:to_i).sort
+      variants_to_a variants
+    end
+
+    def update_outgoing_variants(variants, permitted, variant_id, value)
+      if !incoming_variant_ids.include? variant_id
+        # When a variant has been removed from incoming but remains
+        # in outgoing, remove it from outgoing too
+        variants[variant_id] = false
+
+      elsif permitted.include? variant_id
+        variants[variant_id] = value
+      end
+
+      variants
     end
 
     def incoming_variant_ids
       @order_cycle.supplied_variants.map &:id
     end
+
+    def variants_to_a(variants)
+      variants.select { |k, v| v }.keys.map(&:to_i).sort
+    end
   end
 end