DEPRECATED: use gem_home instead

chgems

chroot for RubyGems.

Features

Sets $GEM_HOME to $project/.gem/$ruby/$version, isolating installed gems to the project directory.
Updates $PATH and $GEM_PATH, providing access to both project gems and user / system installed gems.
- Makes bundle exec obsolete.
Runs a sub-shell or another command.
Plays nicely with chruby, rbenv and rbfu.
Supports bash and zsh.
Small (~50 LOC).
Has tests.

Install

wget -O chgems-0.3.2.tar.gz https://github.com/postmodern/chgems/archive/v0.3.2.tar.gz
tar -xzvf chgems-0.3.2.tar.gz
cd chgems-0.3.2/
sudo make install

PGP

All releases are PGP signed for security. Instructions on how to import my PGP key can be found on my blog. To verify that a release was not tampered with:

wget https://raw.github.com/postmodern/chgems/master/pkg/chgems-0.3.2.tar.gz.asc
gpg --verify chgems-0.3.2.tar.gz.asc chgems-0.3.2.tar.gz

Homebrew

chgems can also be installed with homebrew:

brew install https://raw.github.com/postmodern/chgems/master/homebrew/chgems.rb

Examples

chgems into a project:

$ cd ~/project
$ chgems
Entering /home/hal/project with gems in .gem/ruby/1.9.3/ ...
$ gem env
RubyGems Environment:
  - RUBYGEMS VERSION: 1.8.24
  - RUBY VERSION: 1.9.3 (2012-04-20 patchlevel 194) [x86_64-linux]
  - INSTALLATION DIRECTORY: /home/hal/project/.gem/ruby/1.9.3
  - RUBY EXECUTABLE: /usr/bin/ruby
  - EXECUTABLE DIRECTORY: /home/hal/project/.gem/ruby/1.9.3/bin
  - RUBYGEMS PLATFORMS:
    - ruby
    - x86_64-linux
  - GEM PATHS:
     - /home/hal/project/.gem/ruby/1.9.3
     - /home/hal/.gem/ruby/1.9.1
     - /usr/share/gems
     - /usr/local/share/gems
  - GEM CONFIGURATION:
     - :update_sources => true
     - :verbose => true
     - :benchmark => false
     - :backtrace => false
     - :bulk_threshold => 1000
     - "gem" => "--no-rdoc"
  - REMOTE SOURCES:
     - http://rubygems.org/

chgems into a directory:

$ chgems ~/project

chgems into a directory, run a command and return:

$ chgems ~/project rspec

Cleaning up a chgems project:

$ rm -rf project

Caveat

If you load a Ruby switcher/manager in ~/.bashrc or ~/.zshrc and a .ruby-version file is present, it will override the $GEM_HOME and $GEM_PATH set by chgems. The workaround to this conflict is to simply load the Ruby switcher/manager in ~/.bash_profile or ~/.zprofile.

Alternatives

Credits

mpapis for reviewing the code.