"brew upgrade" fails with "Error: Version must not be empty"

[llimllib]

Output of brew config

HOMEBREW_VERSION: 4.3.11-3-g38e47ea
ORIGIN: https://github.com/Homebrew/brew
HEAD: 38e47ea9964a6991125d44a373a7de038b70ee10
Last commit: 15 minutes ago
Core tap HEAD: 04fbd71d56ad72b201449d1d1ad96a3510673957
Core tap last commit: 6 months ago
Core tap JSON: 29 Jul 14:47 UTC
Core cask tap HEAD: 1a98cd7bf4117c79d6c79916d06cb9223b084844
Core cask tap last commit: 6 months ago
Core cask tap JSON: 29 Jul 14:47 UTC
HOMEBREW_PREFIX: /opt/homebrew
HOMEBREW_BAT_THEME: ansi
HOMEBREW_CASK_OPTS: []
HOMEBREW_EDITOR: /opt/homebrew/bin/nvim
HOMEBREW_MAKE_JOBS: 12
HOMEBREW_SORBET_RUNTIME: set
Homebrew Ruby: 3.3.4 => /opt/homebrew/Library/Homebrew/vendor/portable-ruby/3.3.4/bin/ruby
CPU: dodeca-core 64-bit arm_blizzard_avalanche
Clang: 15.0.0 build 1500
Git: 2.42.0 => /opt/homebrew/bin/git
Curl: 8.6.0 => /usr/bin/curl
macOS: 14.5-arm64
CLT: 15.3.0.0.1.1708646388
Xcode: 15.4
Rosetta 2: false

Output of brew doctor

$ brew doctor
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:
  neofetch
  openssl@1.1
  python-packaging

Description of issue

brew upgrade fails with `Error: Version must not be empty", similar to the report in this issue, which is marked fixed by this issue but nowhere is there a mention of what to do as a user stuck in this situation.

How can I upgrade homebrew?

brew upgrade --verbose doesn't tell me anything useful as far as I can see:

brew upgrade --verbose output

$ brew upgrade --verbose
Error: Version must not be empty
/opt/homebrew/Library/Homebrew/version.rb:497:in `initialize'
/opt/homebrew/Library/Homebrew/vendor/bundle/ruby/3.3.0/gems/sorbet-runtime-0.5.11495/lib/types/private/methods/call_validation.rb:167:in `bind_call'
/opt/homebrew/Library/Homebrew/vendor/bundle/ruby/3.3.0/gems/sorbet-runtime-0.5.11495/lib/types/private/methods/call_validation.rb:167:in `validate_call_skip_block_type'
/opt/homebrew/Library/Homebrew/vendor/bundle/ruby/3.3.0/gems/sorbet-runtime-0.5.11495/lib/types/private/methods/call_validation.rb:109:in `block in create_validator_slow_skip_block_type'
/opt/homebrew/Library/Homebrew/attestation.rb:86:in `new'
/opt/homebrew/Library/Homebrew/attestation.rb:86:in `block in gh_executable'
/opt/homebrew/Library/Homebrew/extend/kernel.rb:534:in `with_env'
/opt/homebrew/Library/Homebrew/attestation.rb:83:in `gh_executable'
/opt/homebrew/Library/Homebrew/vendor/bundle/ruby/3.3.0/gems/sorbet-runtime-0.5.11495/lib/types/private/methods/call_validation.rb:270:in `bind_call'
/opt/homebrew/Library/Homebrew/vendor/bundle/ruby/3.3.0/gems/sorbet-runtime-0.5.11495/lib/types/private/methods/call_validation.rb:270:in `validate_call'
/opt/homebrew/Library/Homebrew/vendor/bundle/ruby/3.3.0/gems/sorbet-runtime-0.5.11495/lib/types/private/methods/_methods.rb:277:in `block in _on_method_added'
/opt/homebrew/Library/Homebrew/attestation.rb:114:in `sort_formulae_for_install'
/opt/homebrew/Library/Homebrew/vendor/bundle/ruby/3.3.0/gems/sorbet-runtime-0.5.11495/lib/types/private/methods/call_validation.rb:270:in `bind_call'
/opt/homebrew/Library/Homebrew/vendor/bundle/ruby/3.3.0/gems/sorbet-runtime-0.5.11495/lib/types/private/methods/call_validation.rb:270:in `validate_call'
/opt/homebrew/Library/Homebrew/vendor/bundle/ruby/3.3.0/gems/sorbet-runtime-0.5.11495/lib/types/private/methods/_methods.rb:277:in `block in _on_method_added'
/opt/homebrew/Library/Homebrew/cmd/upgrade.rb:137:in `run'
/opt/homebrew/Library/Homebrew/vendor/bundle/ruby/3.3.0/gems/sorbet-runtime-0.5.11495/lib/types/private/methods/call_validation.rb:270:in `bind_call'
/opt/homebrew/Library/Homebrew/vendor/bundle/ruby/3.3.0/gems/sorbet-runtime-0.5.11495/lib/types/private/methods/call_validation.rb:270:in `validate_call'
/opt/homebrew/Library/Homebrew/vendor/bundle/ruby/3.3.0/gems/sorbet-runtime-0.5.11495/lib/types/private/methods/_methods.rb:277:in `block in _on_method_added'
/opt/homebrew/Library/Homebrew/brew.rb:95:in `<main>'
Please report this issue:
  https://docs.brew.sh/Troubleshooting

[carlocab]

Can you run it with --debug, as in brew upgrade --verbose --debug?

[llimllib]

in case it's useful, here's the full /opt/homebrew/Cellar/gh/HEAD-53c36d0/.brew/gh.rb:

───────┬────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
       │ File: /opt/homebrew/Cellar/gh/HEAD-53c36d0/.brew/gh.rb
───────┼────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
   1   │ class Gh < Formula
   2   │   desc "GitHub command-line tool"
   3   │   homepage "https://github.com/cli/cli"
   4   │   url "https://github.com/cli/cli/archive/v2.34.0.tar.gz"
   5   │   sha256 "d872d2e9a934aefce0e9873033fee3aa160a6079af73598b7f8d04c4a3d15a7e"
   6   │   license "MIT"
   7   │ 
   8   │   head "https://github.com/cli/cli.git", branch: "trunk"
   9   │ 
  10   │   livecheck do
  11   │     url :stable
  12   │     strategy :github_latest
  13   │   end
  14   │ 
  15   │   depends_on "go" => :build
  16   │ 
  17   │   def install
  18   │     with_env(
  19   │       "GH_VERSION" => version.to_s,
  20   │       "GO_LDFLAGS" => "-s -w -X main.updaterEnabled=cli/cli",
  21   │     ) do
  22   │       system "make", "bin/gh", "manpages"
  23   │     end
  24   │     bin.install "bin/gh"
  25   │     man1.install Dir["share/man/man1/gh*.1"]
  26   │     generate_completions_from_executable(bin/"gh", "completion", "-s")
  27   │   end
  28   │ 
  29   │   test do
  30   │     assert_match "gh version #{version}", shell_output("#{bin}/gh --version")
  31   │     assert_match "Work with GitHub issues", shell_output("#{bin}/gh issue 2>&1")
  32   │     assert_match "Work with GitHub pull requests", shell_output("#{bin}/gh pr 2>&1")
  33   │   end
  34   │ end

[carlocab]

Seems like a bug in brew. Please file an issue at Homebrew/brew.

In the meantime, as a workaround, you can install a non-HEAD version of gh with

brew uninstall gh
brew install gh

or disable attestation verification with

export HOMEBREW_NO_VERIFY_ATTESTATIONS=1

[woodruffw]

Ah yeah, this looks like a hasty assumption on our part about gh --version always having a numeric version. I'll look at a fix. CCing @nandahkrishna for visibility as well.

[woodruffw]

I've opened Homebrew/brew#17899 to fix the proximate error here. You'll still need to either upgrade gh or opt-out of the attestations beta per @carlocab's note, however.

[llimllib]

• I ran brew uninstall gh && brew install gh and then brew upgrade was able to succeed
• I filed "brew upgrade" fails with "Error: Version must not be empty" brew#17898 for this issue
• Thank you both for the help, and for the quick PR with a fix!