cmd/list: add --desc flag

[InspiratioNULL]

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---

Changes

• Add a --desc flag to brew list to print descriptions for the selected formulae and/or casks.
• Extend brew list --json=v2 so each formula and cask entry includes a desc field.
• Refactor the output_json_v2 formula selection logic to remove a duplicated branch.
• Update Sorbet RBI so Homebrew::Cmd::List::Args exposes desc?.

Motivation

I'm working on a multi package manager project, and noticed certain data was straightforward to obtain via the following commands:

• pkgsrc: pkgin avail || pkgin list
• MacPorts: port info --name --description all

Previously, the closest option was brew info --eval-all --json=v2, which includes a lot of
extra data. The new brew list behavior gives:

• Human-readable descriptions:

  brew list --eval-all --desc
  brew list --eval-all --formula --desc
  brew list --eval-all --cask --desc
  brew list --desc
  

(--eval-all = all packages whether installed or not)

I think it is a useful addition to Homebrew, can be used to pipe into other commands in useful ways. After my initial introduction to the macOS platform a couple years ago, and Homebrew as well. I've an avid Homebrew user ever since and I am pleased to contribute to Homebrew!

Note:

Testing

==> brew typecheck
No errors! Great job.

==> brew style --changed --fix
Inspecting 33 files
.................................

33 files inspected, no offenses detected

==> brew tests --changed

  - Note: `evaluates all casks with --eval-all --json=v2` timed out locally (`Timeout::ExitException`),
    other `cmd/list` examples passed.

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Honor list --json default and v1 outputs

The new run case only emits JSON when json_version returns :v2; --json (which maps to :default) and --json=v1 now fall through to legacy_list and print the normal text listing. The CLI description still promises JSON output with v1 as the default, so brew list --json/--json=v1 will no longer return JSON at all.

Useful? React with 👍 / 👎.

[chatgpt-codex-connector]

--desc --cask dumps all casks instead of installed set

In list_descriptions, the --cask branch always loads Cask::Cask.all(eval_all: true) when no names are provided, even without --eval-all. That means brew list --cask --desc now scans and prints descriptions for every available cask rather than the installed casks that brew list --cask would normally show, producing incorrect and extremely large output.

Useful? React with 👍 / 👎.