1 files changed, 16 insertions, 0 deletions
diff --git a/app/models/concerns/mentionable.rb b/app/models/concerns/mentionable.rb
index 7e56e371b27..5ac56ac6fa0 100644
--- a/app/models/concerns/mentionable.rb
+++ b/app/models/concerns/mentionable.rb
@@ -78,6 +78,8 @@ module Mentionable
 
   # Extract GFM references to other Mentionables from this Mentionable. Always excludes its #local_reference.
   def referenced_mentionables(current_user = self.author)
+    return [] unless matches_cross_reference_regex?
+
     refs = all_references(current_user)
     refs = (refs.issues + refs.merge_requests + refs.commits)
 
@@ -87,6 +89,20 @@ module Mentionable
     refs.reject { |ref| ref == local_reference }
   end
 
+  # Uses regex to quickly determine if mentionables might be referenced
+  # Allows heavy processing to be skipped
+  def matches_cross_reference_regex?
+    reference_pattern = if project.default_issues_tracker?
+                          ReferenceRegexes::DEFAULT_PATTERN
+                        else
+                          ReferenceRegexes::EXTERNAL_PATTERN
+                        end
+
+    self.class.mentionable_attrs.any? do |attr, _|
+      __send__(attr) =~ reference_pattern
+    end
+  end
+
   # Create a cross-reference Note for each GFM reference to another Mentionable found in the +mentionable_attrs+.
   def create_cross_references!(author = self.author, without = [])
     refs = referenced_mentionables(author)