brew upgrade doesn't update casks, but brew upgrade --cask <cask> does

[daegalus]

Output of brew config

HOMEBREW_VERSION: 4.6.18-23-g3a1ad1d
ORIGIN: https://github.com/Homebrew/brew
HEAD: 3a1ad1dc8cebca12ce1244a5d3c5919efe579430
Last commit: 3 hours ago
Branch: main
Core tap HEAD: e27ac9ecf1a2b283bcf15b27436df25166f6a694
Core tap last commit: 4 hours ago
Core tap JSON: 22 Oct 10:42 UTC
HOMEBREW_PREFIX: /home/linuxbrew/.linuxbrew
HOMEBREW_CASK_OPTS: []
HOMEBREW_DISPLAY: :0
HOMEBREW_EDITOR: micro
HOMEBREW_FORBID_PACKAGES_FROM_PATHS: set
HOMEBREW_MAKE_JOBS: 32
HOMEBREW_NO_ENV_HINTS: set
HOMEBREW_SORBET_RUNTIME: set
SUDO_ASKPASS: /usr/libexec/openssh/gnome-ssh-askpass
Homebrew Ruby: 3.4.5 => /var/home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/vendor/portable-ruby/3.4.5/bin/ruby
CPU: 32-core 64-bit alderlake
Clang: 21.1.3
Git: 2.51.1 => /home/linuxbrew/.linuxbrew/bin/git
Curl: 8.11.1 => /bin/curl
Kernel: Linux 6.15.10-200.fc42.x86_64 x86_64 GNU/Linux
OS: Bluefin (Version: 42.20250921.1) (Deinonychus)
Host glibc: 2.41
Host libstdc++: 6.0.34
/usr/bin/gcc: 15.2.1
/usr/bin/ruby: N/A
glibc: N/A
gcc@12: N/A
gcc: 15.2.0
xorg: N/A

Output of brew doctor

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Uncommitted files:
   M Casks/v/visual-studio-code.rb

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Description of issue

I wasn't sure if this went here, or in Linux or if it's a bug in brew.

I am currently working on a bunch of casks for Bluefin and other ublue Linux distros. This is work we are doing to identify gaps in Linux support for casks and formulas, and I will be contributing upstream to improve things. Including merging our linux casks for existing applications with the macos ones.

The tap can be found here: https://github.com/ublue-os/homebrew-tap

This issue seems to affect all of our casks, but I am not sure if this is a tap/cask implementation error, or something else.

But as the title says, when we update our casks and push everything up, if someone does brew update the tap updates accordingly. But if you do brew upgrade afterwords, nothing happens. But if you individually upgrade a cask, there is an update and it does it.

Example:

The visual-studio-code-linux cask. I currently have the 1.104.0 version installed, and the 1.105.1 is the current cask version.

> brew upgrade

> brew upgrade visual-studio-code-linux --cask
==> Upgrading 1 outdated package:
ublue-os/tap/visual-studio-code-linux 1.104.0 -> 1.105.1
==> Upgrading visual-studio-code-linux
==> Downloading https://update.code.visualstudio.com/1.105.1/linux-x64/stable

> brew info visual-studio-code-linux --cask
==> visual-studio-code-linux: 1.105.1 (auto_updates)
https://code.visualstudio.com/
Installed
/home/linuxbrew/.linuxbrew/Caskroom/visual-studio-code-linux/1.104.0 (432.9MB)
  Installed on 2025-09-17 at 10:42:29
From: https://github.com/ublue-os/homebrew-tap/blob/HEAD/Casks/visual-studio-code-linux.rb
...

I want to ask for help to remedy this, so that updates work properly, and users get updates when they happen, automatically.

[ZhongRuoyu]

https://docs.brew.sh/FAQ#why-arent-some-apps-included-during-brew-upgrade answers your question. TL;DR: pass brew upgrade --greedy if you want to update casks that have its own auto-update mechanism auto_updates true.

[daegalus]

Oh... I think I fundamentally misunderstood what auto_updates true means.

I thought it just meant it can update freely when there is a cask version update. I now understand that i means it has its own update mechanism and brew should not update it?

That just means i need to remove all the auto_updates entries i have.

Thank you, I think you just solved our problem.

[ZhongRuoyu]

You can refer to the cask cookbook for a more detailed description of what auto_updates does.

Specifically. the auto_updates stanza:

Asserts that the cask artifacts auto-update. Use if Check for Updates… or similar is present in an app menu, but not if it only opens a webpage and does not do the download and installation for you.