Rails RJS render throwing mysterious render error in Princely plugin

WARNING: Rails techie stuff

if you keep seeing this

 NoMethodError (undefined method `[]’ for :update:Symbol):
    /vendor/plugins/princely/lib/pdf_helper.rb:11:in `render’
 

when your controller is doing this:

render :update do
…
end

It’s because of a bug in the Princely plugin when it wraps the standard render method. I have emailed the maintainer (the bug tracker is broken and I did mention it in the email too) but he never bothered to reply. For the record you need to tinker with your plugin code:

Go to the offending line (11) in the plugin code (as per the error message) and change it to

     if options.nil? or ( not options.is_a? Hash ) or options[:pdf].nil?

This stops it assuming that the options is necessarily a Hash and getting upset. Probably a more elegant solution out there in Ruby land but it works for me.