Programmatically determining whether a formula is up to date; and revisions?

[koterpillar]

Output of brew config

HOMEBREW_VERSION: 5.0.10
ORIGIN: https://github.com/Homebrew/brew
HEAD: d5856148ee2fdd810dd864f27297d53509860050
Last commit: 4 days ago
Branch: stable
Core tap JSON: 16 Jan 09:13 UTC
Core cask tap JSON: 16 Jan 09:13 UTC
HOMEBREW_PREFIX: /opt/homebrew
HOMEBREW_CASK_OPTS: []
HOMEBREW_DOWNLOAD_CONCURRENCY: 24
HOMEBREW_EDITOR: nvim
HOMEBREW_FORBID_PACKAGES_FROM_PATHS: set
HOMEBREW_MAKE_JOBS: 12
Homebrew Ruby: 3.4.8 => /opt/homebrew/Library/Homebrew/vendor/portable-ruby/3.4.8/bin/ruby
CPU: dodeca-core 64-bit arm_lobos
Clang: 17.0.0 build 1700
Git: 2.52.0 => /opt/homebrew/bin/git
Curl: 8.7.1 => /usr/bin/curl
macOS: 26.2-arm64
CLT: 26.2.0.0.1.1764812424
Xcode: N/A
Rosetta 2: false

Output of brew doctor

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Warning: Some installed formulae are deprecated or disabled.
You should find replacements for the following formulae:
  icu4c@77

Warning: Unbrewed dylibs were found in /usr/local/lib.
If you didn't put them there on purpose they could cause problems when
building Homebrew formulae and may need to be deleted.

Unexpected dylibs:
  /usr/local/lib/libcrypto.3.dylib
  /usr/local/lib/libykcs11.2.7.2.dylib
  /usr/local/lib/libykpiv.2.7.2.dylib
  /usr/local/lib/libz.1.dylib

Warning: Unbrewed header files were found in /usr/local/include.
If you didn't put them there on purpose they could cause problems when
building Homebrew formulae and may need to be deleted.

Unexpected header files:
  /usr/local/include/openssl/*
  /usr/local/include/ykpiv/*
  /usr/local/include/zlib.h

Warning: Unbrewed '.pc' files were found in /usr/local/lib/pkgconfig.
If you didn't put them there on purpose they could cause problems when
building Homebrew formulae and may need to be deleted.

Unexpected '.pc' files:
  /usr/local/lib/pkgconfig/ykcs11.pc
  /usr/local/lib/pkgconfig/ykpiv.pc

Warning: Unbrewed static libraries were found in /usr/local/lib.
If you didn't put them there on purpose they could cause problems when
building Homebrew formulae and may need to be deleted.

Unexpected static libraries:
  /usr/local/lib/libykcs11.a
  /usr/local/lib/libykpiv.a

Warning: Homebrew's "sbin" was not found in your PATH but you have installed
formulae that put executables in /opt/homebrew/sbin.
Consider setting your PATH for example like so:
  echo 'export PATH="/opt/homebrew/sbin:$PATH"' >> ~/.zshrc

Description of issue

I need to programmatically determine whether a particular formula/cask is up to date or not.

Currently I am using brew info --json=v2 <formula> and parsing the result:

• versions.stable, together with versions.revision, give the latest version
• installed[0].version gives the installed version

However, as of right now brew info --json=v2 git has this output (only relevant fields shown):

{
  "name": "git",
  "installed": [
    {
      "version": "2.52.0_1"
    }
  ],
  "versions": {
    "stable": "2.52.0",
    "head": "HEAD",
    "bottle": true
  }
}

The versions are different: 2.52.0 vs. 2.52.0_1.

Yet Git is up to date by the understanding of brew upgrade, brew outdated, etc.

How do I get the "up to date" answer from brew info (or other machine parseable output)?

[SMillerDev]

How about brew outdated --json?

[koterpillar]

I found "revision": 1 on the top level of the output. This matches what I want with a spot check across several packages.