Running brew info on custom formula tries to download non-existent JSON from official Homebrew servers

[PatTheMav]

Output of brew config

HOMEBREW_VERSION: 4.6.2-2-gcd5cd2d
ORIGIN: https://github.com/Homebrew/brew
HEAD: cd5cd2d04db19038c00052c5b057cd872a75bf30
Last commit: 64 minutes ago
Branch: main
Core tap JSON: 11 Aug 20:14 UTC
Core cask tap JSON: 11 Aug 20:14 UTC
HOMEBREW_PREFIX: /opt/homebrew
HOMEBREW_BAT_THEME: base16-256
HOMEBREW_CASK_OPTS: []
HOMEBREW_EDITOR: /opt/homebrew/bin/vim
HOMEBREW_GITHUB_API_TOKEN: set
HOMEBREW_INSTALL_BADGE: 💻 
HOMEBREW_MAKE_JOBS: 10
HOMEBREW_NO_ENV_HINTS: set
HOMEBREW_SORBET_RUNTIME: set
HOMEBREW_VERBOSE_USING_DOTS: set
Homebrew Ruby: 3.4.5 => /opt/homebrew/Library/Homebrew/vendor/portable-ruby/3.4.5/bin/ruby
CPU: deca-core 64-bit arm_firestorm_icestorm
Clang: 17.0.0 build 1700
Git: 2.50.1 => /opt/homebrew/bin/git
Curl: 8.7.1 => /usr/bin/curl
macOS: 15.6-arm64
CLT: 16.4.0.0.1.1747106510
Xcode: 16.4
Rosetta 2: false

Output of brew doctor

Your system is ready to brew.

Description of issue

I run my own third party tap with customised variants of some core formulas (mainly to keep build options that created unreasonable support burden while they were still part of the official formulas).

I also have a local shell script that runs brew info for my custom variant and the official variant to compare their version numbers and warn me if the core formula has seen an update.

Starting today I noticed that this call reported an error because it tried to download the Formula JSON for my tapped formula:

==> Downloading https://formulae.brew.sh/api/formula/vim-custom.json
Error: Failure while executing; `/usr/bin/env /opt/homebrew/Library/Homebrew/shims/shared/curl --disable --cookie /dev/null --globoff --user-agent Homebrew/4.6.2-2-gcd5cd2d\ \(Macintosh\;\ arm64\ Mac\ OS\ X\ 15.6\)\ curl/8.7.1 --header Accept-Language:\ en --fail --progress-bar --remote-time --output /Users/***/Library/Caches/Homebrew/api/formula/vim-custom.json --location --disable --cookie /dev/null --globoff --show-error --user-agent Homebrew/4.6.2-2-gcd5cd2d\ \(Macintosh\;\ arm64\ Mac\ OS\ X\ 15.6\)\ curl/8.7.1 --header Accept-Language:\ en --fail --progress-bar --compressed --speed-limit 100 --speed-time 5 https://formulae.brew.sh/api/formula/vim-custom.json` exited with 56. Here's the output:
curl: (56) The requested URL returned error: 404

It's obvious why this request has to fail, because the JSON file for my custom formula will not exist on the Homebrew server, but I don't remember brew info ever failing because of this before.

[p-linnane]

I bisected this and found it was introduced in Homebrew/brew@480eeb4. @Rylan12 would you mind taking a look here?

[Rylan12]

Thanks for the ping! This is fixed by Homebrew/brew#20428

[p-linnane]

@PatTheMav Running brew update will get you v4.6.3 which contains the fix for this. Thanks for the report!

[PatTheMav]

Can confirm issue is fixed.