From: Simon Strandgaard <neoneye@...>
Date: 2004-03-24T01:09:30+09:00
Subject: Re: rubygems working with non-gems libs?

On Tue, 23 Mar 2004 16:02:21 +0100, Simon Strandgaard wrote:
> On Tue, 23 Mar 2004 15:40:19 +0100, Raphael Bauduin wrote:
> [snip]
>> I had to add this before to make it find log4r:
>> require "rubygems"
>> require_gem "log4r"
>> 
>> Does that mean that if I start using rubygems, I'll have to edit 
>> ruby code not based on gems?
> 
> 
> Place this file within Ruby's path and set the env variable.
[snip] 
> 
> Then you should be able to do it.


Ok.. I have cleaned up the require-hack code a little bit.

remember to do

setenv RUBYOPT "rhack"


here is the code 

server> ruby test_hack.rb
Loaded suite TestHack
Started
.....
Finished in 0.071033 seconds.

4 tests, 5 assertions, 0 failures, 0 errors
server> expand -t2 test_hack.rb 
require 'test/unit'
require 'stringio'
require 'hack'

class TestHack < Test::Unit::TestCase
  def test_loaderror
    e = assert_raise(LoadError) do
      require 'nonexisting'
    end
    assert_match(/^No such file to load -- nonexisting$/, e.message)
  end
  def test_old_require
    require 'observer'      # is shipped with Ruby
  end
  def test_gem_require
    require 'progressbar'   # is shipped with rubygems
  end
  def capture_stderr(&block)
    e = StringIO.new
    $stderr = e
    block.call
    return e.string
  ensure
    $stderr = STDERR
  end
  def test_failed_loadgem
    path = $:.clone
    $:.clear
    output = capture_stderr do
      e = assert_raise(LoadError) do
        require 'progressbar'   # is shipped with rubygems
      end
      assert_match(/^No such file to load -- progressbar$/, e.message)
    end
    assert_match(/Hack/, output)
  ensure
    $:.concat(path)
  end
end

if $0 == __FILE__
  require 'test/unit/ui/console/testrunner'
  Test::Unit::UI::Console::TestRunner.run(TestHack)
end
server> expand -t2 hack.rb 
module Kernel
  alias old_require require 
  def require(filename)
    begin
      old_require(filename)
    rescue LoadError => old_e
      begin
        old_require("rubygems")
      rescue LoadError
        $stderr.puts <<-MSG.gsub(/^\s*/, "")
        Hack which loads "rubygems" when Ruby starts up, failed
        to find "rubygems". You may want to either install
        "rubygems" or remove this hack from the RUBYOPT envvar.
        MSG
        raise old_e
      end
      begin
        require_gem(filename)
      rescue LoadError
        raise old_e
      end
    end
  end
end # module Kernel
server>


--
Simon Strandgaard