class RuboCop::Cop::InternalAffairs::RedundantDescribedClassAsSubject

def on_block(node)
  return unless (described_class_arguments = described_class_subject?(node))
  return if described_class_arguments.count >= 2
  describe = find_describe_method_node(node)
  unless (exist_config = describe.last_argument.source == ':config')
    additional_message = ' and specify `:config` in `describe`'
  end
  message = format(MSG, additional_message: additional_message)
  add_offense(node, message: message) do |corrector|
    corrector.remove(range_by_whole_lines(node.source_range, include_final_newline: true))
    corrector.insert_after(describe.last_argument, ', :config') unless exist_config
  end
end