R – Errors when trying to update ruby gems from 2.0.1

There is no need to take such drastic steps as completely rebuilding Ruby, reinstalling Rubygems from scratch or installing a version manager to solve this problem. There is simply a dependency cycle introduced by the release of hoe 2.3.0:

rubygems-update 1.3.5 requires (among other things) hoe-seattlerb
hoe-seattlerb requires hoe >= 2.3.0
hoe >= 2.3.0 requires rubygems >= 1.3.1

I wrote the blog post linked to by zipizap. To recap:

1. If you've already tried to update, uninstall the latest rubygems-update first: sudo gem uninstall rubygems-update -v 1.3.5
2. Update to 1.3.0: sudo gem install rubygems-update -v 1.3.0
3. sudo update_rubygems
4. Then update to latest: sudo gem update --system

With the release of Rubygems 1.3.6, it looks like this problem may be gone. From the release notes:

• Development deps are no longer added to rubygems-update gem so older versions can update sucessfully.

Try setting GEM_HOME and GEM_PATH to ~/.gem,

For the current terminal session, just type:

export GEM_HOME=~/.gem
export GEM_PATH=~/.gem

If you want these to be set whenever you open a terminal, add the above commands to your ~/.bashrc file.

For a more comprehensive solution to setting up a custom ruby environment, see this tutorial from Site5KB, which describes using a .gemrc file.