parse_visibility

# File lib/rdoc/parser/ruby.rb, line 1511
  def parse_visibility(container, single, tk)
    singleton = (single == SINGLE)

    vis_type = tk.name

    vis = case vis_type
          when 'private'   then :private
          when 'protected' then :protected
          when 'public'    then :public
          when 'private_class_method' then
            singleton = true
            :private
          when 'public_class_method' then
            singleton = true
            :public
          when 'module_function' then
            singleton = true
            :public
          else
            raise RDoc::Error, "Invalid visibility: #{tk.name}"
          end

    skip_tkspace_comment false

    case peek_tk
      # Ryan Davis suggested the extension to ignore modifiers, because he
      # often writes
      #
      #   protected unless $TESTING
      #
    when TkNL, TkUNLESS_MOD, TkIF_MOD, TkSEMICOLON then
      container.ongoing_visibility = vis
    else
      new_methods = []

      case vis_type
      when 'module_function' then
        args = parse_symbol_arg
        container.set_visibility_for args, :private, false

        container.methods_matching args do |m|
          s_m = m.dup
          s_m.record_location @top_level
          s_m.singleton = true
          new_methods << s_m
        end
      when 'public_class_method', 'private_class_method' then
        args = parse_symbol_arg

        container.methods_matching args, true do |m|
          if m.parent != container then
            m = m.dup
            m.record_location @top_level
            new_methods << m
          end

          m.visibility = vis
        end
      else
        args = parse_symbol_arg
        container.set_visibility_for args, vis, singleton
      end

      new_methods.each do |method|
        case method
        when RDoc::AnyMethod then
          container.add_method method
        when RDoc::Attr then
          container.add_attribute method
        end
        method.visibility = vis
      end
    end
  end