"Unintialized constant" error when I do brew info <cask>

[gwerbin]

I get the following error when I run brew info for any cask:

Error: uninitialized constant Cask::Cmd::AbstractCommand
Please report this issue:
  https://docs.brew.sh/Troubleshooting
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/cask/cmd/info.rb:11:in `<class:Cmd>'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/cask/cmd/info.rb:7:in `<module:Cask>'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/cask/cmd/info.rb:6:in `<top (required)>'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/vendor/portable-ruby/2.6.3_2/lib/ruby/2.6.0/rubygems/core_ext/kernel_require.rb:54:in `require'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/vendor/portable-ruby/2.6.3_2/lib/ruby/2.6.0/rubygems/core_ext/kernel_require.rb:54:in `require'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/cmd/info.rb:341:in `info_cask'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/cmd/info.rb:146:in `block in print_info'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/cmd/info.rb:139:in `each'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/cmd/info.rb:139:in `each_with_index'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/cmd/info.rb:139:in `print_info'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/cmd/info.rb:102:in `info'
/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/brew.rb:122:in `<main>'

I'm not sure when the problem started, as I haven't tried to run brew info for a cask on Linux in at least a week.

I tried running brew update-reset && brew update but the problem persists.

brew doctor output:

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: Some installed formulae are deprecated or disabled.
You should find replacements for the following formulae:
  isl@0.18

brew config output:

HOMEBREW_VERSION: 3.0.2-16-ge143dfd
ORIGIN: https://github.com/Homebrew/brew
HEAD: e143dfdad6bbd4cd178906eccac5de095c80dc2f
Last commit: 20 minutes ago
Core tap ORIGIN: https://github.com/Homebrew/linuxbrew-core
Core tap HEAD: 6c10145e41a01117170ff0ddabd08e76adf7a12b
Core tap last commit: 2 hours ago
Core tap branch: master
HOMEBREW_PREFIX: /home/linuxbrew/.linuxbrew
HOMEBREW_CASK_OPTS: []
HOMEBREW_DISPLAY: :0
HOMEBREW_EDITOR: nvim
HOMEBREW_MAKE_JOBS: 8
Homebrew Ruby: 2.6.3 => /home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/vendor/portable-ruby/2.6.3_2/bin/ruby
CPU: quad-core 64-bit skylake
Clang: 11.1 build (parse error)
Git: 2.30.1 => /usr/bin/git
Curl: 7.74.0 => /usr/bin/curl
Kernel: Linux 5.10.16-1-default x86_64 GNU/Linux
OS: openSUSE Tumbleweed
Host glibc: 2.33
/usr/bin/gcc: 10.2.1
/usr/bin/ruby: 2.7.2
glibc: N/A
gcc@5: N/A
xorg: N/A

[jonchang]

/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/cmd/info.rb:341:in `info_cask'

If you add a line here to also require "cask/cmd" does this fix your issue? This is likely a bug but it's not clear to me why you would want to run brew info for casks on Linux so I want to make sure all of your use-cases are covered.

[gwerbin]

/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/cmd/info.rb:341:in `info_cask'

If you add a line here to also require "cask/cmd" does this fix your issue? This is likely a bug but it's not clear to me why you would want to run brew info for casks on Linux so I want to make sure all of your use-cases are covered.

Yes, that fixes the problem!

My use case was originally that I wanted to get the URLs (and lists of artifacts) from various font casks so that I could download them manually, as per #877. It turns out that I don't need to do this anymore because the Linuxbrew/fonts tap exists. But occasionally I am still on my Linux machine and I want to get info about a Cask for later use on my Mac.

[jonchang]

Ok, thanks. I've opened Homebrew/brew#10678 to fix this issue.