What tool runs during a "cd" and checks the .ruby_version file? - ruby

I've installed a bunch of tools related to ruby recently. Macports ruby19 (then uninstalled per advice here on SO), then installed RVM and ruby-1.9.3-p.
Now I notice that I get a message when I cd or even \cd into a directory with a .ruby-version file that I do not have the matching version of ruby installed. And it's driving me crazy: what tool is performing this check?
The only thing that I can see that rvm did to my environment is to append ~/.rvm/bin onto my path. I'm running "terminal" on OS X Mountain Lion.
edit: is there some way to tell bash to echo all processes launched from a shell command?

The cd is overwritten by RVM.
.ruby-version is a "standard" used by RVM/rbenv/chruby to allow you to switch to project specific Ruby.
You can fix this problem in two ways:
Make RVM install all missing rubies:
echo rvm_install_on_use_flag=1 >> ~/.rvmrc
Make RVM install Ruby for current project:
rvm use . --install

Related

Trying to uninstall and fresh install Ruby on Ubuntu: do I still have Ruby installed?

I'm coming from Windows to Linux (Ubuntu) so I'm new to the CLI. I had issues trying to install Rails so I figured a fresh install would help. I'm following "Installing Ruby the Correct Way."
I thought I had uninstalled Ruby, but after installing 2.1.4 it still shows some Ruby folders. Have I completely uninstalled Ruby?
Downloading ruby-2.1.4.tar.gz...
-> http://dqw8nmjcqpjn7.cloudfront.net/bf9952cdeb3a0c6a5a27745c9b4c0e5e264e92b669b2b08efb363f5156549204
Installing ruby-2.1.4...
Installed ruby-2.1.4 to /home/richard/.rbenv/versions/2.1.4
richard#richard-ThinkPad-T400:~$ rbenv global 2.1.4
richard#richard-ThinkPad-T400:~$ ruby -v
The program 'ruby' can be found in the following packages:
* ruby
* ruby1.8
Try: sudo apt-get install <selected package>
richard#richard-ThinkPad-T400:~$ sudo rbenv global 2.1.4
richard#richard-ThinkPad-T400:~$ ruby -v
The program 'ruby' can be found in the following packages:
* ruby
* ruby1.8
Try: sudo apt-get install <selected package>
Are the "the following packages" on my local system? or are they online?
EDIT
I've been getting this error when I try to install RVM (and some other applications):
GPG signature verification failed for '/home/richard/.rvm/archives/rvm-1.26.0.tgz' - 'https://github.com/wayneeseguin/rvm/releases/download/1.26.0/1.26.0.tar.gz.asc'!
try downloading the signatures:
gpg --keyserver hkp://keys.gnupg.net --recv-keys D39DC0E3
they can be compared with:
https://rvm.io/mpapis.asc
https://keybase.io/mpapis
Does this have anything to do with it? I wouldn't really think so but I'm a noob.
Don't sudo rbenv anything or you will summon Cthulhu. Use rbenv by itself.
Also, don't randomly follow guides on the internet until you're more familiar with your OS; They go stale, or start out wrong, or don't accurately apply to what you're doing. Instead, go to the source and follow the directions there.
To find out what is installed on your machine, use locate to quickly find Ruby instances. Something like:
locate /bin/ruby | grep -v .rbenv
should narrow down whether multiple Rubies are installed outside the ~/.rbenv directory.
Traditionally, you'll find a normally installed system-wide Ruby in /usr/bin/ruby. A user installed one from source will probably be in /usr/local/bin/ruby unless you specifically said otherwise, probably with a PREFIX= directive.
rbenv will default to installing Ruby in the ~/.rbenv hierarchy since it acts like a sandbox manager and will put all Rubies it installs underneath that directory. RVM, a similar application, will use ~/.rvm, and in both cases, the purpose is to keep them where the user's permissions are sufficient to install and update gems without requiring the use of sudo. For general use, avoid sudo unless you understand what you're about to do, as it can turn a computer into an under-desk heater in seconds.
The shell uses the PATH variable to figure out where to look for executable commands. It sounds like your PATH isn't set correctly. If you followed the directions on the rbenv site, they say how to enable rbenv by modifying your ~/.bash_profile script. Doing that, then closing and reopening your shell should bring rbenv to life.
Following that blog post, you are installing Ruby using a tool called rbenv, and if you only uninstalled one Ruby, that doesn't mean that all Rubies are uninstalled.
The message that you posted shows that it is a local install: Installed ruby-2.1.4 to /home/richard/.rbenv/versions/2.1.4 which is a copy of the 4th line of your message.
You can find out from whence your Ruby executable is being invoked by issuing at the command line:
which ruby
You will then know if the program is available and which it is. Using ruby -v if it is there will tell you the version.
You have done some of these steps and are finding out that your system does not know how to get to the Ruby, if it is indeed installed.
Right now, it is effectively uninstalled, as it is unavailable to your environment.

Accidentally deleted many hidden files with "git clean -fd" and now I cannot install Ruby

So I really messed up on this one.....
I was working on a rails application and wanted to revert back to a previous commit. I opened a new shell and forgot to cd into my projects folder, so I ran "git reset --hard" and then "git clean -fd" in my user directory. I noticed before everything was gone, but here is what got deleted:
bash-3.2$ git clean -fd
Removing .CFUserTextEncoding
Removing .Trash/
Removing .Xauthority
Removing .adobe/
Removing .bash_history
Removing .bash_profile
Removing .bundle/
Removing .config/
Removing .cups/
Removing .dropbox/
Removing .fontconfig/
Removing .gem/
Removing .gitconfig
Removing .guard_history
Removing .heroku/
Removing .irb-history
Removing .irb_history
Removing .lesshst
Removing .macports/
^C
I was able to save my project in that shell, but I (now realized stupidly) thought restarting my computer would be best once I realized my rails and bundle commands were not working in another shell. Unfortunately I lost that working shell which I through researching realize would have helped.
What is done is done, and I am trying to fix everything, but something I cannot get right is installing ruby. I am using rbenv to install ruby but even after installing it, it won't register with in any shell:
-bash-3.2$ rbenv local
2.1.1
-bash-3.2$ ruby -v
-bash: ruby: command not found
I am a bit inexperienced when it comes to the terminal and I am freaking out. I am wondering if I should restore factory settings. My important pictures and documents are backed up but I don't use time machine.
I don't know if it is just ruby which is the problem, so far nothing else has been an issue, but I would appreciate any help solving the problem!
EDIT
So I realize now that the issue was deleting my bash_profile which has had all sorts of knock on effects. I really don't know how to fix or reset it....I am trying to uninstall everything and reinstall it but I am having trouble figuring out what. I tried installing ruby via mac ports, which worked, but it was not sending the message to rbenv.
I suggest HomeBrew to install rbenv. It has worked better for me than MacPorts did.
This older post Modern Ruby Development (on Mac) is still very helpful.
The install for HomeBrew needs ruby, which will be a problem for you as you have lost ruby.
ruby -e "$(curl -fsSL https://raw.github.com/Homebrew/homebrew/go/install)"
The rbenv lines you need in your .bash_profile, according to the rbenv install docs, are,
export PATH="$HOME/.rbenv/bin:$PATH"
eval "$(rbenv init -)"
Do not forget to say, source .bash_profile after editing the profile, or open a new terminal.
If your rbenv command is no longer available, you can install it directly from git with,
git clone https://github.com/sstephenson/rbenv.git ~/.rbenv
That is assuming the git command still works.
With the rbenv lines restored to your .bash_profile, you might be able to install a ruby with,
rbenv install 2.1.1
(rbenv install -l will list available versions. Any of the lines output from there can go after rbenv install.)
Finally, use rbenv global to set the default ruby to one of the rbenv installed ones.
rbenv global 2.1.1
You can view the current global ruby set for rbenv with,
rbenv global
As you know,
ruby -v
will get the version of the ruby that runs by default. You might not know that,
which ruby
will tell you where the shell finds that ruby command in your path.

After installing jekyll, getting -bash: jekyll command not found

hey there jekyll users... I am new to using ruby/rvm and have followed the instructions to install it on my mac locally, and then installed the jekyll gem, but when i try to run jekyll commands I get
bash: jekyll: command not found
Any advice?
I know that when I installed rvm, (or maybe it was during the homebrew install), I received a notice that I have both .profile and .bash_profile and it asked me to add source ~/.profile to .bash_profile could that be the problem?
I've also tried installing using this command gem install --source http://rubygems.org jekyll
and it says it installs but when I try jekyll in the terminal, I keep getting command not found.
If there is any more information I need to post to help, please let me know.
I know that when I installed rvm, (or maybe it was during the homebrew install), I received a notice that I have both .profile and .bash_profile and it asked me to add source ~/.profile to .bash_profile could that be the problem?
Yes. Do what it said there and you should have access to the jekyll command.
user$ echo "source $HOME/.rvm/scripts/rvm" >> ~/.bash_profile
I read most of the solutions around the web and most of them seem to suggest a $PATH change. I don't like to edit my path unless I have to so I just did a symbolic link:
ln -s /usr/local/Cellar/ruby/2.0.0-p247/lib/ruby/gems/2.0.0/gems/jekyll-1.2.1/bin/jekyll
Here's an updated answer for 2020 (soon 2021).
One of the reasons you can get "command not found" after installing gems is because they were installed in a location that your bash shell does not yet know about. The way the computer looks up commands is by looking at the PATH, which is a list of folders where the computer should look for commands, such as jekyll.
The location of the gems depends on how you installed Ruby, and since there are many ways to install Ruby on a Mac, how to fix the "command not found" error will depend on how you installed Ruby. If you used a Ruby manager, such as RVM, rbenv, or chruby, then you might have missed a step in the installation instructions. They typically take care of the PATH for you automatically with a script. If you installed Ruby with Homebrew, then you'll need to add /usr/local/lib/ruby/gems/2.7.0/bin to your PATH, for example:
echo 'export PATH="/usr/local/opt/ruby/bin:/usr/local/lib/ruby/gems/2.7.0/bin:$PATH"' >> ~/.bash_profile
(Replace .bash_profile with .zshrc if you are using zsh. If you're not sure which shell you're using, read this: https://www.moncefbelyamani.com/which-shell-am-i-using-how-can-i-switch/)
I strongly believe that there should only be one recommended way to install Ruby, which is with a Ruby manager. I prefer chruby because it's the lightest and easiest to use. I wrote a script that will automatically set up a proper Ruby environment for you with chruby, including updating your PATH and everything else that is necessary to be able to install gems and use them right away without getting any errors.
You can read more about my script and other ways to fix the "command not found" error in these articles:
https://www.moncefbelyamani.com/troubleshooting-command-not-found-in-the-terminal/
https://www.moncefbelyamani.com/how-to-install-jekyll-on-a-mac-the-easy-way/
https://www.moncefbelyamani.com/the-definitive-guide-to-installing-ruby-gems-on-a-mac/

Jekyll - command not found

I am trying to get Jekyll running but I have no experience with Ruby.
As far as I can tell the installation of Jekyll has succeeded.
However:
$ jekyll
Gives an error:
-bash: jekyll: command not found
This is the gem env result:
- RUBYGEMS VERSION: 1.3.4
- RUBY VERSION: 1.8.7 (2010-01-10 patchlevel 249) [universal-darwin10.0]
- INSTALLATION DIRECTORY: /Volumes/HDD/DADU/gems
- RUBY EXECUTABLE: /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby
- EXECUTABLE DIRECTORY: /Volumes/HDD/DADU/gems/bin
- RUBYGEMS PLATFORMS:
- ruby
- universal-darwin-10
- GEM PATHS:
- /Volumes/HDD/DADU/gems
- /Volumes/HDD/DADU/.gem/ruby/1.8
- /Library/Ruby/Gems/1.8
- /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/gems/1.8
- GEM CONFIGURATION:
- :update_sources => true
- :verbose => true
- :benchmark => false
- :backtrace => false
- :bulk_threshold => 1000
- REMOTE SOURCES:
- http://gems.rubyforge.org/
And I found the following paths leading to "something" Jekyll:
~.gem/ruby/1.8/gems/jekyll-0.11.0/lib/jekyll.rb
~.gem/ruby/1.8/gems/bin/jekyll (exec file)
If you are using MacOS, from the Troubleshooting guide:
Jekyll & Mac OS X 10.11Permalink
With the introduction of System Integrity Protection, several directories that were previously writable are now considered system locations and are no longer available. Given these changes, there are a couple of simple ways to get up and running. One option is to change the location where the gem will be installed (again, using sudo only if necessary):
$ gem install -n /usr/local/bin jekyll
For others coming here with the following set up:
OS X + brewed install of ruby + (possibly) zsh
I figured the problem is that after installing jekyll as per their instructions, gem installs the jekyll gem in the brew cellar, not where the OS usually expects it (somehwere in a gem directory for ruby).
So, all that was needed here was to find out where the brew install of ruby installs gems, locate the jekyll binary, and create a symbolic link to it in /usr/bin.
Here is are the steps I took to fix it:
Type gem env and look for GEM PATHS. For me it was:
/usr/local/Cellar/ruby/1.9.3-p194/lib/ruby/gems/1.9.1.
Make sure you can see the jekyll binary in the directory from 1 above and copy its path (if you can't, search any other paths listed in GEM PATHS for it). For me it was:
/usr/local/Cellar/ruby/1.9.3-p194/lib/ruby/gems/1.9.1/gems/jekyll-1.4.3/bin/jekyll
Use the path from step 2 above to create a symlink to /usr/bin/jekyll. I did it by typing this (you might need sudo to create the symlink):
cd /usr/bin && ln -s /usr/local/Cellar/ruby/1.9.3-p194/lib/ruby/gems/1.9.1/gems/jekyll-1.4.3/bin/jekyll jekyll
Now all should be merry if you type jekyll.
The easiest method of doing this is to use RVM. It manages Ruby and all its gems for you and it's easy to use. See this link for using it.
If you did not want to use that you will need to modify your PATH variables so it can find your gems. I have found this to be tedious and reverted to RVM, but here are the general steps.
You will need to find out where your gems are getting installed. If you did gem install ... the gems will be in ~/.gem/ruby/1.8/gems/bin, if you used sudo gem install ... the gems will be somewhere in /System/Library/Frameworks/Ruby.framework/Versions/1.8/Resources
You have to add this path to your PATH variable. Easiest way to do this is by running :
echo 'PATH=$PATH:above/path/to/gems' >> ~/.bash_profile
If you are using RBENV instead of RVM you simply need to run rehash in the command line after installing jekyll:
rbenv rehash
I installed my ruby2.6.0 and gem via brew on MacOS 10.14.
For me, add the following line to my ~/.zshrc solved this issue.
export PATH=/usr/local/lib/ruby/gems/2.6.0/bin:$PATH
I found jekyll executable file with command locate jekyll.
Maybe a little late, but...
I had some trouble to install Jekyll on Ubuntu and tried everything that people answered in this thread - unfortunately nothing worked.
Then, I watched a video on Jekyll's site and after installing the whole ruby package again, sudo gem install jekyll worked.
Try it before anything else:
sudo apt-get update
sudo apt-get install ruby-full
sudo gem install jekyll
jekyll -v
It seems pretty simple, but it works on Ubuntu.
One solution would be editing your ~/.bashrc file and add this line:
PATH=$PATH:~/.gem/ruby/1.8/gems/bin
This will add ~/.gem/ruby/1.8/gems/bin in Bash's lookup path.
Reopen the terminal and it should work. Or you can use the following command:
. ~/.bashrc
Following steps solved my problem
gem uninstall jekyll
sudo gem install jekyll
Open ~/.bash_profile and add this code in the last line,
export PATH=$PATH:/usr/local/lib/ruby/gems/1.9.1/gems/jekyll-2.5.2/bin
Save and close the .bash_profile
Close and reopen the mac terminal, try running jekyll now, it should work
For me, I followed this installation guide instead of their main page's installation instruction. It worked after I changed the bash_profile file and restarted Terminal.
Jekyll is a ruby gem : Ruby gems in linux, for example, are in /var/lib/gems/1.8, as can be seen in the "ruby env" output.
Thus, you need to add the executables in this directory to your path.
In general, if a ruby gem is "not found" by your OS, it simply indicates that either
1) You don't have the gem installed or
2) You don't have the gem installed in a directory that is on your path.
I have found that there have been a few issues with installing ruby and ruby gems on linux (I have found that it can be tricky on Ubuntu v10, and have confirmed this with the Ruby folks on IRC). Thus, tools like RVM or rbenv might be the best approach to setting up a stable, maintainable ruby environment.
Easier than creating a symlink just install it correctly.
If you got permission errors like a lot of people are getting when trying to use
gem install jekyll
instead use
sudo gem install jekyll
#jayunit100,
I'm running into the same issue with a Jekyll blog. I've installed the gem via RVM in a 'Blog directory and the _config.yml file says that it should generate into Blog/_site. Is it as simple as adding Blog to the PATH or is there something else I'm missing?
Update: My bad, I didn't really have the gem installed. Lesson learned: rvm requirements and brew doctor are there for a reason - before you install stuff USE THEM
In my case I had to run bundle install --force
Then bundle exec jekyll serve works, but jekyll serve still doesn't. It seems I'll have to go with the former from now on…
When you use the --user-install option, RubyGems will install the gems to a directory inside your home directory, something like ~/.gem/ruby/1.9.1. The commands provided by the gems you installed will end up in ~/.gem/ruby/1.9.1/bin. For the programs installed there to be available for you, you need to add ~/.gem/ruby/1.9.1/bin to your PATH environment variable.
For example, if you use bash you can add that directory to your PATH by adding code like this to your ~/.bashrc file:
if which ruby >/dev/null && which gem >/dev/null; then
PATH="$(ruby -r rubygems -e 'puts Gem.user_dir')/bin:$PATH"
fi
https://guides.rubygems.org/faqs/#user-install
I put it in the .bash_profile (Mac OS X).
https://hathaway.cc/2008/06/how-to-edit-your-path-environment-variables-on-mac/
Here's an updated answer for 2020 (soon 2021). To install any Ruby gem, whether it's Jekyll, Bundler, Rails, etc., you need a proper Ruby development environment on a Mac. There are various ways to install Ruby on a Mac, as I have written about in great detail in my definitive guide to installing Ruby gems on a Mac. The only one I recommend is to use a Ruby manager because it's the most flexible and sets you up for success for the long term. My preferred one is chruby because it's the lightest and easiest to use. As part of installing Ruby, you also need to properly configure your shell startup file (typically ~/.zshrc or ~/.bash_profile) so that it knows where to find the gems you install. Otherwise, you'll get the "command not found" error, which I've also written about.
Since there are several steps involved in setting up a working Ruby development environment on a Mac, I wrote some scripts to automate the whole process and make things easier and faster for people. You can read more about the scripts in my guide mentioned above.
I had this problem for a very stupid reason, which is that I was working on Linux and had installed both flatpak and .deb versions of Visual Studio Code. I was confused because I could successfully run bundle exec jekyll serve in the terminal application, but not from the integrated terminal in Visual Studio Code.
Well, it turns out the integrated terminal loaded my PATH correctly in the .deb version but not the flatpak one. So... if you, like me, have foolishly installed multiple versions of Visual Studio Code, check which one you are using.
This is what worked for me. I'm not developing in ruby, and don't have a lot of tools that I use it for, so I don't need RVM. I also don't need to install jekyll as root. I just want it to run.
(This answer is just a more descriptive version of answers by Santa Zhang, jayunit100, and a few others.)
1. Find Local Gem Path
> gem env
Assuming this runs, it will list a bunch of useful information. You are looking for GEM PATHS. If there are two, then you want the one that is found in your home directory. Mine was something like /home/<user>/.local/share/gem/ruby/3.0.0
If it doesn't run, install the ruby gem program and try again.
2. Find Gem Binaries Path
Look in that directory until you find the location where the jekyll executable is actually installed. I found it in /home/<user>/.local/share/gem/ruby/3.0.0/bin/jekyll. But what I need is the directory path, not the file, so: /home/<user>/.local/share/gem/ruby/3.0.0/bin/.
3. Add That to PATH
Figure out how to add a directory to your PATH environment variable. Instructions for that are too extensive to provide here, as it depends on your operating system and preferred shell, and the versions of the same. Search for that information elsewhere on Stackoverflow.
4. Restart Your Session
Close your terminal and open a new one. Make sure the directory was added to your path. Depending on how you set your PATH variable, you might need to log out of your session and log in again.

Installing Ruby gems not working with Home Brew

The gems I install via sudo gem install ... can't be executed (I get a command not found).
They seem to install into /usr/local/Cellar/ which is Brew's install directory (also, the gems in /Library/Ruby/ don't work either). Is there anything else I need to do to make the gems executable? I'm using ZSH on Mac OS X 10.6 with Ruby v1.8 for the one in Brew.
EDIT: It seems to be working now. I just went out for a few hours and came back to try it again.
Homebrew is nice. However unlike brew and npm, gem does not make aliases in /usr/local/bin automatically.
Solution
I went for a very simple approach (as of March 2020):
# Based on "`brew --prefix ruby`/bin"
export PATH=/usr/local/opt/ruby/bin:$PATH
# Based on "`gem environment gemdir`/bin"
export PATH=/usr/local/lib/ruby/gems/3.0.0/bin:$PATH
Add this to your .bashrc (or .bash_profile, .zshrc, etc.).
That's it! Now all Ruby bins and installed gems will be available from your shell!
In older versions of Homebrew (before 2017), there was a separate package for Ruby 2 called ruby20, for which you'd use the following snippet instead:
export PATH=/usr/local/opt/ruby20/bin:$PATH
This line was the only line needed at the time. But, in Ruby 2.1 the gems got moved to a separate directory. No longer under /usr/local/opt/ruby/bin, but instead at /usr/local/lib/ruby/gems/2.0.0/bin (where "2.0.0" is the last major Ruby version for Gem's purposes).
How it works
Homebrew keeps track of where it installed a package, and maintains a symbolic link for you that points there.
$ brew --prefix ruby
/usr/local/opt/ruby
$ l /usr/local/opt/ruby
/usr/local/opt/ruby# -> ../Cellar/ruby/2.5.3_1
Effectively, adding /usr/local/opt/ruby to PATH is the same as the following:
export PATH=/usr/local/Cellar/ruby/2.5.3_1/bin:$PATH
Except, this long version hardcodes the currently installed version of Ruby and would stop working next time you upgrade Ruby.
As for Gem, the following command will tell you the exact directory Gem adds new packages to:
$ gem environment gemdir
/usr/local/lib/ruby/gems/2.7.0
Tools
These tools were meant to automatically bridge between Homebrew and Gem:
josh/brew-gem (no longer exists)
indirect/brewbygems (unmaintained)
I haven't used these but they might work for you.
brew unlink ruby; brew link ruby might add symlinks to /usr/local/bin/:
$ which sass
$ brew unlink ruby; brew link ruby
Unlinking /usr/local/Cellar/ruby/2.0.0-p0... 20 links removed
Linking /usr/local/Cellar/ruby/2.0.0-p0... 31 symlinks created
$ which sass
/usr/local/bin/sass
brew --prefix ruby is still pretty slow, but you could also just add /usr/local/opt/ruby/bin to the path.
$ time brew --prefix ruby
/usr/local/opt/ruby
0.216
$ time brew --prefix ruby
/usr/local/opt/ruby
0.076
$ stat -f%Y /usr/local/opt/ruby
../Cellar/ruby/2.0.0-p0
I like home brew. There's probably a better way to do this, but if you run:
gem environment
That will print out a nice list of all the relevant paths. Look for the one labeled EXECUTABLE DIRECTORY. That's the one you want to add to your path. In my case that's /usr/local/Cellar/ruby/1.9.3-p362/bin/ruby but I would imagine it would change with newer version of Ruby.
I'm using /bin/bash as my shell, but the process of adding it to your path should be pretty much the name.
I use TextWrangler (via the command line tools) to edit my .profile file. To do that, it's just:
edit ~/.profile
When your done, either close your terminal and open a new one, or run:
source ~/.profile
Using the info in Timo's answer, I've got this:
PATH=/usr/local/opt/ruby/bin:$PATH
GEMSDIR=$(gem environment gemdir)/bin
PATH=$GEMSDIR:$PATH
export PATH
Works for Homebrew, works for the separate gems directory, and doesn't hardcode a Ruby version.
You can be fine with ruby installed by homebrew too.. You just lack the functionality of custom gemsets with homebrew.
first do:
sudo nano /etc/paths
this will bring up nano editor,
then add the following to the paths:
/usr/local/Cellar/ruby/1.9.3-p194/bin
your version of ruby will probably vary.
Thats it. It should now detect your gems.
Oh, btw, you need to Ctrl+X > y > ENTER to save a file in nano.
Instead of using => $(cd $(which gem)/..; pwd)
You could use this instead => $(brew --prefix ruby)/bin
I think this evolve a bit.
Just add
export PATH=/usr/local/opt/ruby/bin:$PATH
To your .bashrc (or .bash_profile, .zshrc/.bashrc, .. – whatever you use).
If you have a problem with ruby itself
brew unlink ruby
brew link ruby

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