Discourse Theme CLI (console app to help you build themes)

I’m getting the following running “discourse_theme new mytheme” on mac

/Library/Ruby/Gems/2.3.0/gems/discourse_theme-0.3.0/lib/discourse_theme/cli.rb:62:in run': undefined methodempty?’ for Dir:Class (NoMethodError)
from /Library/Ruby/Gems/2.3.0/gems/discourse_theme-0.3.0/bin/discourse_theme:5:in <top (required)>' from /usr/local/bin/discourse_theme:22:inload’
from /usr/local/bin/discourse_theme:22:in `’

It looks like you’re running an old version of Ruby. We recommend using 2.6.2 at the moment. Dir.empty? was added in ruby 2.4.