LibIdn FFI ruby binding

sudo apt-get install libidn11

Gemfile:

gem 'idn_ffi'

IDNFFI.to_ascii "топ-site.рф"
=> "xn---site-iyehw.xn--p1ai"

IDNFFI.to_unicode "xn---site-iyehw.xn--p1ai"
=> "топ-site.рф"