file 'lib' not found when installing rails 3.1 on Mac OS X Lion

I just installed rvm and then rails 3.1rc5 with:

gem install rails --pre

But I got some errors after "Installing ri documentation" and the RDoc documentation:

Successfully installed <bunch of things>
30 gems installed
Installing ri documentation for multi_json-1.0.3...
Installing ri documentation for actives开发者_开发技巧upport-3.1.0.rc5...
Installing ri documentation for builder-3.0.0...
unable to convert "\xF1" from ASCII-8BIT to UTF-8 for README, skipping
unable to convert "\xF1" from ASCII-8BIT to UTF-8 for README.rdoc, skipping
Installing ri documentation for i18n-0.6.0...
Installing <tons more documentation>
Installing ri documentation for rails-3.1.0.rc5...
file 'lib' not found
Installing RDoc documentation for multi_json-1.0.3...
Installing RDoc documentation for activesupport-3.1.0.rc5...
Installing RDoc documentation for builder-3.0.0...
unable to convert "\xF1" from ASCII-8BIT to UTF-8 for README, skipping
unable to convert "\xF1" from ASCII-8BIT to UTF-8 for README.rdoc, skipping
Installing RDoc documentation for i18n-0.6.0...
Installing <tons more documentation>
Installing RDoc documentation for rails-3.1.0.rc5...
file 'lib' not found

The README file issues don't seem to be a big deal, but the 'lib' file not found sounds a bit scary.. why is it doing that? Some searching revealed others having this problem and fixing it with gem install rdoc and then re-running gem install rails --pre. But that still gives the same lib file missing errors for me.

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Try using rvm gemset install rails --pre

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I installed 3.1.0 on Windows (not rc8, but the final release), and got the "file 'lib' not found" error, installing both ri and RDoc. When I type in 'which ruby', I see it installed in the c:/ruby192/bin directory. I had to create a .rvm directory for myself -- it was not created as part of the install.

the --no-rdoc --no-ri worked, of course. The --pre commands installed rc8 instead of the final release.

What gives?

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Installing RDoc fixed this problem for me. I had to do this in the gemset I was using.

rvm use rubyversion@gemset
gem install rdoc

After this I could install gems without the "file 'lib' not found" error.

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I had the same problem with rails 3.0.9 on my Mac OS X Lion and the "rvm gemset install rails" trick solved it !

$ rvm gemset install rails
installing rails ...
rails  installed.
$ rails -v
Rails 3.0.9

Thanks !

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I had a similar issue before, while my solution was this: try to use ruby 1.9.2-head instead of ruby 1.9.2-p290.

rvm install ruby-1.9.2-head
rvm use ruby-1.9.2-head --default

And then, install rails 3.1 again.