module RuboCop::Cop::Heredoc

def delimiter_string(node)
  return '' unless (match = node.source.match(OPENING_DELIMITER))
  match.captures[1]
end

def heredoc_type(node)
  return '' unless (match = node.source.match(OPENING_DELIMITER))
  match.captures[0]
end

def indent_level(str)
  indentations = str.lines.map { |line| line[/^\s*/] }.reject { |line| line.end_with?("\n") }
  indentations.empty? ? 0 : indentations.min_by(&:size).size
end

def on_heredoc(_node)
  raise NotImplementedError
end

def on_str(node)
  return unless node.heredoc?
  on_heredoc(node)
end