[DRE-maint] Bug#677147: ruby-redcarpet FTBFS ./test/redcarpet_test.rb:12:in `require': no such file to load -- nokogiri (LoadError)

[peter green]

package: ruby-redcarpet
severity: serious
version: 2.1.1-1
tags: patch

ruby-redcarpet failed to build on all autobuilders that had tried to build it at the time of writing and also failed in my amd64 pbuilder.

>Rewriting shebang line of /build/buildd-ruby-redcarpet_2.1.1-1-armel-YKFnOe/ruby-redcarpet-2.1.1/debian/ruby-redcarpet/usr/bin/redcarpet
>/usr/bin/ruby1.8 -I/usr/lib/ruby/vendor_ruby /usr/lib/ruby/vendor_ruby/gem2deb/test_runner.rb
>./test/redcarpet_test.rb:12:in `require': no such file to load -- nokogiri (LoadError)
>	from ./test/redcarpet_test.rb:12
>	from -e:1:in `require'
>	from -e:1
>	from -e:1:in `each'
>	from -e:1
>ERROR: Test "ruby1.8" failed. Exiting.
>dh_auto_install: dh_ruby --install /build/buildd-ruby-redcarpet_2.1.1-1-armel-YKFnOe/ruby-redcarpet-2.1.1/debian/ruby-redcarpet returned exit code 1

The package builds successfully if ruby-nokogiri is installed, please add it to the build-depends or otherwise fix this bug.