Tonight I created a simple Rip plugin which lets you install a RubyGems stub into the current ripenv, for faking out RubyGems.

Why is this useful? Well, Grit includes the following code:

require 'rubygems'
gem "mime-types", ">=0"
require 'mime/types'

Grit doesn’t really need RubyGems – it just needs mime/types. Trying to run one of Grit’s tests, for instance, fails with mime/types installed through any means other than RubyGems:

$ ruby test/test_diff.rb 
/Library/Ruby/Site/1.8/rubygems.rb:826:in `report_activate_error': 
  Could not find RubyGem mime-types (>= 0) (Gem::LoadError)
  	from /Library/Ruby/Site/1.8/rubygems.rb:260:in `activate'
  	from /Library/Ruby/Site/1.8/rubygems.rb:67:in `gem'
  	from ./test/../lib/grit.rb:20
  	from ./test/helper.rb:1:in `require'
  	from ./test/helper.rb:1
  	from test/test_diff.rb:1:in `require'
  	from test/test_diff.rb:1

But! after installing the plugin we can simply run rip fake_rubygems to stub RubyGems in the active ripenv:

$ rip fake_rubygems
rip: rubygems successfully faked
$ ruby test/test_diff.rb 
Loaded suite test/test_diff
Started
.
Finished in 0.000676 seconds.

Fantastic. Check out the plugin. For now the easiest way to install it is to manually stick it in ~/.rip/rip-commands (after creating the directory).

So basically:

mkdir -p ~/.rip/rip-commands
cd ~/.rip/rip-commands
wget http://is.gd/1Sgvf

Next up: making plugin management simpler. Ta.