(NoMethodError) undefined method `last' for nil:NilClass caused by :markup: directive

[bhenderson]

sorry if this is a dup. I tried looking for other issues.

$ rdoc --version
rdoc 4.0.1
$ cat /tmp/ruby.rb

# :markup: RDoc
class Foo

  ##
  # Cool method

  def cool() end

end

$ rdoc /tmp/ruby.rb --debug # filtered

The internal error was:

        (NoMethodError) undefined method `last' for nil:NilClass

/home/bhenderson/.multiruby/install/2.0.0-p0/lib/ruby/gems/2.0.0/gems/rdoc-4.0.1/lib/rdoc/parser.rb:273:in `use_markup'

the docs say this should be valid

https://github.com/rdoc/rdoc/blob/master/lib/rdoc/markup.rb#L706