Cap recipe to create an rvm gemset before deploy

gistfile1.rb

$:.unshift(File.expand_path('./lib', ENV['rvm_path'])) # Add RVM's lib directory to the load path.
require "rvm/capistrano"                               # Load RVM's capistrano plugin.
set :rvm_ruby_string, "1.8.7@#{application}"           # Or whatever env you want it to run in.

# Make sure the gemset exists before running deploy:setup
def disable_rvm_shell(&block)
  old_shell = self[:default_shell]
  self[:default_shell] = nil
  yield
  self[:default_shell] = old_shell
end

task :create_gemset do
  disable_rvm_shell { run "rvm use #{rvm_ruby_string} --create" }
end

before "deploy:setup", "create_gemset"