Use case. During opal development – ‘stable’ copy installed, but want to test local ‘updated’ copy.

# disable_rubygems-1_9.rb

##
# Remove the automatically loaded RubyGems instance in Ruby 1.9
#
# The best way to run this is using the command-line switch '-r'.
#
# e.g ruby -r./disable_rubygems-1.9
#
# Remember to fully qualify the file name for this script to reflect where you install it.
#
# You can also set the environment variable RUBYOPT to do this every time ruby loads.
#
# e.g. (bash) set RUBYOPT="-r./disable_rubygems-1.9"; export RUBYOPT
#      (tcsh) setenv RUBYOPT "-r./disable_rubygems-1.9"
##

##
# Steps
#  1) Remove appropriate modules
#  2) Clean any automatically loaded gems from the load path
##

rubygems_installed = false
if defined?(Gem) then
  rubygems_installed = true
end

if rubygems_installed

  # Remove the 'gem' method from the Kernel
  module Kernel
    remove_method(:gem)
  end

  # Remove the Gem module - just undefine the constant that references it
  Object.class_eval { remove_const("Gem") }

  # Clean the loadpath of any loaded gems
  $: = $:.reject {|path| path =~ /gem/} 

end

See

git://github.com/tflynn/ruby19-norubygems.git

For a repository that contains patched versions of ruby 1.9 without integrated rubygems support.

As of early-ish 2008-06-29, see branch

patched-svn-17710

Only lightly tested, but seems to work.

So, an explicit “require ‘rubygems’” is no longer required.

e.g. – “require ‘rake’” is now sufficient to load the latest version of the ‘rake’ gem.

The following gems also appear to be included (‘built in’) to Ruby 1.9

• rake 0.8.0

( A little later)

As far as I can see, the pre-1.9.0 rubygems ‘custom require’ hook is no longer used in Ruby 1.9. It appears to be ‘baked in’ to the main Ruby interpreter. (Please, show me I’m wrong!) The consequences:

• Without intervention, ‘require’ will not only search standard ruby libraries, but will always include and automatically load (the most recent) version of a gem that satisfies the name specified in the ‘require’.
• I’ve not (yet) found any way to disable this behavior.
• Anyone who wants to do something other than use rubygems (Oh heresy!) has to either:
  • Try to hook the require (ala Ruby 1.8.x / Rubygems) (Don’t see how)
  • Name their classes/packages with a name other than any standard library or gem name.

If you’ve done something similar to:

./configure –prefix=/usr/local/ruby1.9 –with-readline-dir=/usr/local

Remember to create /usr/local/ruby1.9 before you run ‘sudo make install’

The local mode will need to have an additional ‘require’ to duplicate the hook installed for the system-level install.

• A zip fie
• Three subdirectories
• a zip file containing the actual code
• a zip file ? containing metadata (aka opalspec, frozen dependency tree)
• a zip file ? containing opal version info

• Perform the necessary first-time conversion of the needed gems to opals
• Resolve the dependency tree by hand
• Build a development bootstrap version of opals – e.g. miniopal