class ActiveSupport::Logger

def self.logger_outputs_to?(logger, *sources)

# => true
ActiveSupport::Logger.logger_outputs_to?(logger, STDOUT)
logger = Logger.new(STDOUT)

Returns true if the logger destination matches one of the sources 
def self.logger_outputs_to?(logger, *sources)
  logdev = logger.instance_variable_get("@logdev")
  logger_source = logdev.dev if logdev.respond_to?(:dev)
  sources.any? { |source| source == logger_source }
end