Latest homebrew doctor said the /opt/homebrew is not writeable

[ngthphat]

I installed homebrew on my Mac M1 in a few months back, it works without any issues.

Today, I accidentally ran the homebrew install script. Then, whenever I instal whatever package, it always failed with this error

 phat.nguyen@Phats-MacBook-Pro  ~    brew tap homebrew/core
Error: /opt/homebrew is not writable. You should change the
ownership and permissions of /opt/homebrew back to your
user account:
  sudo chown -R $(whoami) /opt/homebrew
==> Tapping homebrew/core
fatal: could not create work tree dir '/opt/homebrew/Library/Taps/homebrew/homebrew-core': Permission denied
Error: Failure while executing; `git clone https://github.com/Homebrew/homebrew-core /opt/homebrew/Library/Taps/homebrew/homebrew-core --origin=origin --template=` exited with 128.

I tried to run the uninstall script, and re-install the homebrew, but the issue still there.

The installation happens smoothly without issue. However, when I run `brew doctor, this is what I got

Please note that these warnings are just used to help the Homebrew maintainers
with debugging if you file an issue. If everything you use Homebrew for is
working fine: please don't worry or file an issue; just ignore this. Thanks!

Warning: The following directories are not writable by your user:
/opt/homebrew
/opt/homebrew/etc/bash_completion.d
/opt/homebrew/share/doc
/opt/homebrew/share/man
/opt/homebrew/share/man/man1
/opt/homebrew/share/zsh
/opt/homebrew/share/zsh/site-functions
/opt/homebrew/var/homebrew/locks

You should change the ownership of these directories to your user.
  sudo chown -R $(whoami) /opt/homebrew /opt/homebrew/etc/bash_completion.d /opt/homebrew/share/doc /opt/homebrew/share/man /opt/homebrew/share/man/man1 /opt/homebrew/share/zsh /opt/homebrew/share/zsh/site-functions /opt/homebrew/var/homebrew/locks

And make sure that your user has write permission.
  chmod u+w /opt/homebrew /opt/homebrew/etc/bash_completion.d /opt/homebrew/share/doc /opt/homebrew/share/man /opt/homebrew/share/man/man1 /opt/homebrew/share/zsh /opt/homebrew/share/zsh/site-functions /opt/homebrew/var/homebrew/locks

Warning: Missing https://github.com/Homebrew/brew git origin remote.

Without a correctly configured origin, Homebrew won't update
properly. You can solve this by adding the remote:
  git -C "/opt/homebrew" remote add origin https://github.com/Homebrew/brew
==> Tapping homebrew/core
fatal: could not create work tree dir '/opt/homebrew/Library/Taps/homebrew/homebrew-core': Permission denied
Error: Failure while executing; `git clone https://github.com/Homebrew/homebrew-core /opt/homebrew/Library/Taps/homebrew/homebrew-core --origin=origin --template=` exited with 128.
Error: Failure while executing; `/opt/homebrew/bin/brew tap homebrew/core` exited with 1.

I followed the suggestion from the output above. But, nothing got changed.

[carlocab]

I followed the suggestion from the output above. But, nothing got changed.

What was the output of following the suggestions from brew doctor?

[ngthphat]

@carlocab I found the root cause, there is an alias which mapping the brew command with another user. It explains why brew complains about permission.
Thank you for your quick response.

This thread can be closed now.

[ainsliej]

I think I am having the same problem. Could you possibly elaborate on how you fixed the issue?

[cryptphil]

@ainsliej You can check if you have an alias for brew by running alias | grep brew and if it gives you a match just run unalias brew .