gistfile1.rb

require 'irb/completion'
require 'pp'
IRB.conf[:AUTO_INDENT]=true

if defined?(Rails) == 'constant'
  spec_helper = Rails.root + "spec/spec_helper.rb"
  require spec_helper if File.exists?(spec_helper)
end

Alas, I get this annoying warning when I add this to irbrc:

irb: warn: can't alias context from irb_context.

You're right, it is annoying, and it's related to rspec, but I prefer that to having to type require 'spec/spec_helper' every time I run console. Google doesn't offer any great suggestions, so I'm OK to leave it like this.