class RuboCop::Cop::Style::RedundantRegexpConstructor

def on_send(node)
  return unless (regexp, regopt = redundant_regexp_constructor(node))
  add_offense(node, message: format(MSG, method: node.method_name)) do |corrector|
    pattern = regexp.map(&:source).join
    regopt = regopt.join
    corrector.replace(node, "/#{pattern}/#{regopt}")
  end
end