How to get Ruby / Homebrew / RVM to work on Yosemite?

Question

After installing Yosemite, I was unable to run brew or ruby.

I was getting this error on brew update:

/usr/local/bin/brew: /usr/local/Library/brew.r         


        

Answer 1

Take a look at this tutorial here: http://ryantvenge.com/2014/09/ruby-homebrea-yosemite/

It worked for me!

Answer 2

This is a conglomeration from answers from other people's posts as well as a bit of digging on Google, but I figured I'd put it up so a complete answer is in one place. Specifically this gets things to work now, but also lets you do brew updates as normal and gets everything clean again.

1. Open /usr/local/Library/brew.rb (emacs/vi/nano/whatever)
2. Change the first line to read: #!/System/Library/Frameworks/Ruby.framework/Versions/Current/usr/bin/ruby -W0. You're just changing the "1.8" that was in that line to "Current" (make sure you keep the capital "C" otherwise git will get confused later).
3. cd $(brew --repository)
4. git add Library/brew.rb
5. git commit -m "upgrading to ruby 2.0"
6. brew update (or sudo brew update if your brew is setup to only do system changes with sudo)

Credit: a lot of this came from here, though I really recommend against doing git commit -am in your /usr/local folder.

Answer 3

brew update error can be fixed with this:

sudo chown -R $USER:admin /usr/local
cd /usr/local
git reset --hard origin/master
brew update

https://github.com/Homebrew/homebrew/issues/19140

Answer 4

This error can easily be fixed in the following steps:

1) Open terminal

2) Type nano /usr/local/Library/brew.rb

3) In the first line change “1.8″ to “Current”, so it should look like this:

#!/System/Library/Frameworks/Ruby.framework/Versions/Current/usr/bin/ruby -W0

via http://blog.ic3man.gr/2014/06/homebrew-ruby-bad-interpreter-no-such-file-or-directory/

Answer 5

Steps to fix it:

1. Install command line tools for Xcode 6

2. Reinstall brew:

   ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
   

3. Once brew is installed, rvm will work:

   rvm install ruby
   

Worked for me, yahoo!

Answer 6

Note: Only do the below if you end up in a completely failed state, as this is very DANGEROUS

As an example I kept getting

$ sudo ln -s Current 1.8

$ brew update

/usr/local/Library/brew.rb:18:in ': undefined method help?’ for [“update”]:Array (NoMethodError)

I just get this…(no matter what command just switch out “update” with the command) I solved the problem by asking for a buddies /usr/local folder. I then made a backup of my /usr/local folder.

sudo mv /usr/local /usr/local.orig

I then moved his /usr/local to mine

sudo mv ~/Downloads/local /usr/local

Note: You will likely lose some data so make sure to make a backup.