class Rubocop::Cop::FavorSprintf

def on_send(node)
  receiver_node, method_name, *arg_nodes = *node
  if method_name == :% &&
      ([:str, :dstr].include?(receiver_node.type) ||
       arg_nodes[0].type == :array)
    add_offence(:convention, node.loc.expression.line, MSG)
  end
  super
end