https://edgeapi.rubyonrails.org/classes/ActiveSupport/LogSubscriber/TestHelper.html
ActiveSupport::LogSubscriber::TestHelper
Provides some helpers to deal with testing log subscribers by setting up notifications.
activesupporttesthelper
https://api.rubyonrails.org/v4.2.7.1/classes/ActiveSupport/LogSubscriber.html
ActiveSupport::LogSubscriber
activesupport