class RuboCop::Cop::Rails::StripHeredoc

def on_send(node)
  return unless (receiver = node.receiver)
  return unless receiver.type?(:str, :dstr)
  return unless receiver.respond_to?(:heredoc?) && receiver.heredoc?
  register_offense(node, receiver)
end

def register_offense(node, heredoc)
  add_offense(node) do |corrector|
    squiggly_heredoc = heredoc.source.sub(/\A<<(-|~)?/, '<<~')
    corrector.replace(heredoc, squiggly_heredoc)
    corrector.remove(node.loc.dot)
    corrector.remove(node.loc.selector)
  end
end