[WIP] remove call to external ls when loading chruby

[kbrock]

before

/Users/kbrock/dotfiles/bashrc.d/chruby.sh

real	0m0.004s
user	0m0.001s
sys	0m0.001s

after

/Users/kbrock/dotfiles/bashrc.d/chruby.sh

real	0m0.000s
user	0m0.000s
sys	0m0.000s

why?

I was trying to figure out ways to make nvm.sh load faster on my system. chruby loads so much faster, and when I looked to see why, I was distracted by the call to ls -A "$dir". It was using a builtin to list the files in the directory, but an external command to detect if there were files in the directory.

So yea, I converted the already quick method to made it even faster.

• I tested with my files in ~/.rubies, and a non-existent /opt/rubies.
• I did not test this with a directory with a space in the name, but didn't see how that could be possible other than having a PREFIX with a space in the name.
• I did not test with rubies that start with a period, but it looked like the original script did not handle that case either. And it didn't seem valid.

This is yak shaving, and you probably can think up a better implementation. But it seems to work in zsh and bash.

If you prefer not to introduce change (because change always introduces risk), then that is cool. Just close. I just saw this change and wanted to share.

As you will note, nvm is noticeably slower and the reason for my original tangent:

/Users/kbrock/dotfiles/bashrc.d/node.bash

real	0m0.177s
user	0m0.033s
sys	0m0.089s

Thanks again for such a great tool. And it already performs heads and shoulders better than other tools out there. (ruby or other)

refs:

• https://github.com/kbrock/dotfiles/blob/master/bashrc.d/chruby.sh
• https://github.com/kbrock/dotfiles/blob/master/bashrc.d/node.bash (since changed to speed this up)