directory_tree.rb

class Tree < Hash

  def self.glob(path)
    tree = Tree.new
    Dir::glob("#{path}/**/*").sort.each do |dir|
      next unless File.directory? dir
      tree[File.dirname(dir)] ||= []
      tree[File.dirname(dir)] << File.basename(dir)
    end

    tree.render tree.keys.first
  end

  def render(key)
    "<ul>#{child key}</ul>"
  end

  def child(key)
    html = ""
    self[key].each do |dir|
      if self["#{key}/#{dir}"].nil?
        html << "<li>#{dir}</li>"
      else 
        html << render("#{key}/#{dir}")
      end
    end
    html
  end

end


if __FILE__ == $0
  puts Tree.glob("/path/to/dir")
end