with_clean_env does not replace original RUBYLIB environmental variable

[robertclancy]

with_clean_env does not reset the RUBYLIB environmental variable. This results in any calls to bundler in that environment will use the current bundler version. For example, I would expect

bundle _1.10.0_ exec ruby -e "require 'bundler'; Bundler.clean_system('bundle _1.9.1_ exec ruby -e \"require \\'bundler\\'; puts Bundler::VERSION\"')"

to return 1.9.1, but it returns 1.10.0.

[indirect]

The Bundler gem is not loaded from RUBYLIB... perhaps you can give an example that does use RUBYLIB for something?

[indirect]

Whoops; sorry, I misunderstood your example. This is a bug! Thanks for reporting it.

[indirect]

(This was broken by #2536, which changed from using RUBYOPT to using RUBYLIB, but did not update with_clean_env to clean RUBYLIB as well as RUBYOPT).