Fix Rubinius gem binstubs path

[mislav]

Rubinius 2 insists that it installs RubyGems binstubs into PREFIX/gems/bin instead of PREFIX/bin.

This creates complexity for rbenv rehash and exec processes, so we symlink gems/bin into bin and have RubyGems create binstubs at a location that is consistent with other Ruby implementations.

@sstephenson Right now this is done unconditionally. Should we only be doing this when ruby-build is invoked through rbenv-install? I'm wondering whether this might be unwanted by people who use ruby-build for non rbenv-related purposes.

See rbenv/rbenv#178, rbenv/rbenv#461

[stouset]

Perhaps figure out why the Rubinius team did this in the first place, and if there's a way to have rbenv rehash query the current Ruby implementation for its gem bindir.

[mislav]

@stouset They did it so that there is a separation of rbx's gem binstubs from those in PREFIX/bin, in case prefix is a system path like /usr/local. However, I don't find this feature welcome.

Yes, rbenv could very easily query each ruby for its gem bindir. However, we don't want to go down that route since it would slow down the rehash process significantly.

[mislav]

Use this script to fix your existing rbx installs in rbenv. It will symlink gems/bin/ to bin/ for every rbx-* version.

set -e
for prefix in "$(rbenv root)/versions"/rbx-*; do
  gemdir="${prefix}/gems/bin"
  bindir="${prefix}/bin"
  if [ -d "$gemdir" ] && [ ! -L "$gemdir" ]; then
    for file in "$gemdir"/*; do
      [ -x "$file" ] && mv -v "$file" "$bindir"
    done
    rm -rf "$gemdir"
    ln -hvs ../bin "$gemdir"
  fi
done

[john-griffin]

Thanks for fixing this, working with rbx-2.1.1 here.

[designium]

Thanks a lot! The rbx install was painful.

[karabijavad]

@mislav thank you for that script, it is working for me.

does this mean the script will need to be ran anytime a rehash is ran?

[mislav]

With newer rbx installs + newer ruby-build, there is no issue anymore. My script above is just a workaround for people who had existing installs before we sorted this out.

And no, this is a one-time operation. It doesn't need to be run before every rehash.