Mute Specific Deprecation Messages in Rails

So when you're fully aware that something is going to be deprecated in Rails in the next release but it's clogging up your stdout when running your specs, you can mute that specific deprecation message by creating an initializer with

module ActiveSupport  
  class Deprecation
    module Reporting
      # Mute specific deprecation messages
      def warn(message = nil, callstack = nil)
        return if message.match(/Automatic updating of counter caches/)

        super
      end
    end
  end
end  

Do this responsibly of course!