1 files changed, 11 insertions, 16 deletions
diff --git a/app/models/concerns/issuable.rb b/app/models/concerns/issuable.rb
index acb6f5a2998..8e11d4f57cf 100644
--- a/app/models/concerns/issuable.rb
+++ b/app/models/concerns/issuable.rb
@@ -17,7 +17,7 @@ module Issuable
     belongs_to :assignee, class_name: "User"
     belongs_to :updated_by, class_name: "User"
     belongs_to :milestone
-    has_many :notes, as: :noteable, dependent: :destroy do
+    has_many :notes, as: :noteable, inverse_of: :noteable, dependent: :destroy do
       def authors_loaded?
         # We check first if we're loaded to not load unnecessarily.
         loaded? && to_a.all? { |note| note.association(:author).loaded? }
@@ -87,6 +87,12 @@ module Issuable
       User.find(assignee_id_was).update_cache_counts if assignee_id_was
       assignee.update_cache_counts if assignee
     end
+
+    # We want to use optimistic lock for cases when only title or description are involved
+    # http://api.rubyonrails.org/classes/ActiveRecord/Locking/Optimistic.html
+    def locking_enabled?
+      title_changed? || description_changed?
+    end
   end
 
   module ClassMethods
@@ -131,7 +137,10 @@ module Issuable
     end
 
     def order_labels_priority(excluded_labels: [])
-      select("#{table_name}.*, (#{highest_label_priority(excluded_labels).to_sql}) AS highest_priority").
+      condition_field = "#{table_name}.id"
+      highest_priority = highest_label_priority(name, condition_field, excluded_labels: excluded_labels).to_sql
+
+      select("#{table_name}.*, (#{highest_priority}) AS highest_priority").
         group(arel_table[:id]).
         reorder(Gitlab::Database.nulls_last_order('highest_priority', 'ASC'))
     end
@@ -159,20 +168,6 @@ module Issuable
 
       grouping_columns
     end
-
-    private
-
-    def highest_label_priority(excluded_labels)
-      query = Label.select(Label.arel_table[:priority].minimum).
-        joins(:label_links).
-        where(label_links: { target_type: name }).
-        where("label_links.target_id = #{table_name}.id").
-        reorder(nil)
-
-      query.where.not(title: excluded_labels) if excluded_labels.present?
-
-      query
-    end
   end
 
   def today?