class RuboCop::Cop::Rails::PluralizationGrammar

def on_send(node)
  return unless duration_method?(node.method_name) && literal_number?(node.receiver) && offense?(node)
  number, = *node.receiver
  add_offense(node, message: message(number, node.method_name)) do |corrector|
    method_name = node.loc.selector.source
    corrector.replace(node.loc.selector, correct_method(method_name))
  end
end