Add concerns to autoload

config/application.rb

@@ -16,7 +16,7 @@ module Gitlab
     # -- all .rb files in that directory are automatically loaded.
     # Custom directories with classes and modules you want to be autoloadable.
-    config.autoload_paths += %W(#{config.root}/lib)
+    config.autoload_paths += %W(#{config.root}/lib #{config.root}/app/models/concerns)
     # Only load the plugins named here, in the order given (default is alphabetical).
     # :all can be used as a placeholder for all plugins not explicitly named.

spec/lib/issue_commonality_spec.rb → spec/models/concerns/issuable_spec.rb

 require 'spec_helper'
-describe Issue, "IssueCommonality" do
+describe Issue, "Issuable" do
   let(:issue) { create(:issue) }
   describe "Associations" do