Fixed subcategory validation in promotion create

app/controllers/promotions_controller.rb

@@ -30,8 +30,8 @@ class PromotionsController < ApplicationController
     @promotion = Promotion.new(promotion_params)
     @promotion.subcategory_id = nil if !@promotion.nil? && @promotion.subcategory_id.zero?
     source =
-      if @promotion.category_id.present?
-        "a la #{@promotion.subcategory_id.present? ? 'sublínea' : 'línea' } #{@promotion.subcategory_id.present? ? Category.find(@promotion.subcategory_id).category : @promotion.category.category}"
+      if @promotion.category_id.present? || @promotion.subcategory_id.present?
+        "a la #{@promotion.subcategory_id.present? ? 'sublínea' : 'línea'} #{@promotion.subcategory_id.present? ? Category.find(@promotion.subcategory_id).category : @promotion.category.category}"
       elsif @promotion.product.present?
         "al producto #{@promotion.product.name}"
       end