class RuboCop::Cop::Style::NilLambda

def on_block(node)
  return unless node.lambda? || node.proc?
  return unless nil_return?(node.body)
  message = format(MSG, type: node.lambda? ? 'lambda' : 'proc')
  add_offense(node, message: message) do |corrector|
    autocorrect(corrector, node)
  end
end