class RuboCop::Cop::RSpec::SingleArgumentMessageChain

def on_send(node)
  message_chain(node) do |arg|
    return if valid_usage?(arg)
    method = node.method_name
    msg = format(MSG, recommended: replacement(method), called: method)
    add_offense(node.loc.selector, message: msg) do |corrector|
      autocorrect(corrector, node, method, arg)
    end
  end
end