How to make xcode use the correct version of ruby when running a script?

Question

In xcode I have a 'run script' build phase that runs a ruby script. However, it seems that xcode is trying to run it using the default mac 1.8 version of ruby rather than the latest version. Given that the script requires a gem, it's failing with a require error and the path in the error points to /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems/

Obviously the 1.8 in that path is making me suspicious.

If I open up terminal and run the command ruby -v then it correctly returns 2.0.0p0 which I installed and set as default using RVM.

How might I get Xcode to look in the right place? Or am I mis-interpreting this error?

Update:

To give a little more info, here is the exact error that the compiler is throwing:

/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require': no such file to load -- json (LoadError)
    from /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems/custom_require.rb:31:in `require'
from /Volumes/Macintosh HD/Documents/Projects/WesternMusicElements/WesternMusicElements/Ruby/NoteCollectionParser.rb:9
Command /bin/sh failed with exit code 1

Answer 1

You can also do rvm use system which switches to default mac os ruby and then install the gems with sudo. Seemed to be the easiest for me.