#update brew

To update Ruby version, firstly I update RVM and then, found some article about rbenv. https://github.com/sstephenson/rbenv

With rbenv, change ruby version easily. Sounds nice. Since I always check the other people’s code to learn. 

Before install rbenv, need to uninstall RVM.  1.  $ rvm implode (some article says: $ rvm seppuku)   Seppuku!? 

2. rvm asks for re-confirm for uninstall. type “yes”

3. Then, below comment is appeared: 

“Note you may need to manually remove /etc/rvmrc and ~/.rvmrc if they exist still.

Please check all .bashrc .bash_profile .profile and .zshrc for RVM source lines and delete or comment out if this was a Per-User installation.

Also make sure to remove `rvm` group if this was a system installation.

Finally it might help to relogin / restart if you want to have fresh environment (like for installing RVM again).”

Open text editor (I use sublime text to delete all .bashrc .bash_profile .profile and .zshrc for RVM source lines). 

Also, do:  $ rm -rf .rvm    $ rm -rf ./etc/rvmrc to remove RVM files. 

Now, all RVM related files, lines were removed. 

4. Install rbenv using brew  $ brew update (just in case. I already update/upgrade all brew before)  $ brew install rbenv ruby-build $ echo 'eval "$(rbenv init -)"' >> ~/.bash_profile (this command create path.)  $ rbenv install -l (check ruby install list)  $ rbenv install 2.2.3 (this is the current stable version)  5. To set default ruby version   $ rbenv global 2.2.3 (set version 2.2.3 as default version) 

6. To back system default to default   $ rbenv global system (back to system default 2.0.0) 

7. To set a specific version to the local directory  Under the local directory:  $ rbenv local 1.9.3-p448 

To unset local setting:  $ rbenv local --unset 

8. Uninstall ruby  $ rbenv uninstall 1.9.3-p448 

9. rehash plug-in  When instal new version of Ruby or gem package, rbenv require the command of “$ rbenv rehash”. This is too much to do every time. 

$ gem install rbenv-rehash  $ rbenv rehash (after install gem, only 1 time to do rehash)

or install plug-in  $ git clone https://github.com/sstephenson/rbenv-gem-rehash.git ~/.rbenv/plugins/rbenv-gem-rehash This plug in automatically do “rbenv rehash”! 

Reference: 

https://github.com/sstephenson/ruby-build#readme https://mattbrictson.com/rails-osx-setup-guide

I use MAC OSX Yosemite and it comes with Ruby2.0.0.  Current Ruby version is 2.2.3.  I omitted update the version since I am not good for terminal command. But, have to update it! 

Before update Ruby version, I need to update Brew. $ brew update Then, get this error:  error: The following untracked working tree files would be overwritten by merge: so many lists here!!

So, I need to fix this.  To merge the git:  cd $(brew --repository)  git add .  git commit -m ‘brew update’ brew update  Then, get the same error before. 

Then, try:  cd $(brew --repository)  git fetch origin  git reset --hard origin/master brew update 

Still get the same error before!! 

Check Homebrew git site:  https://github.com/Homebrew/homebrew/blob/master/share/doc/homebrew/FAQ.md

Find out what is outdated:  brew outdated  (So many outdated files are listing!)  Upgrade everything:  brew upgrade 

Then, try again  brew update Still get the same error!

Check stackoverflow site:  http://stackoverflow.com/questions/10762859/brew-update-the-following-untracked-working-tree-files-would-be-overwritten-by