Support more URL strategies for Homebrew

[MindTooth]

Tell us more.

https://docs.brew.sh/Formula-Cookbook#url-download-strategies

I have an internal formula that I've distributed in a tap. The formula itself is setup using Git via HTTPS and a Git insteadOf to download via git+ssh@.

One of the format that is not supported is:

url "https://github.com/some/package.git",
    tag:      "v1.6.2",
    revision: "344cd2ee3463abab4c16ac0f9529a846314932a2"

Truth, I need to use the help of Claude for this one. But we've worked together on this following prompt:

Claude Prompt

# Task: Add generic git-URL support to Renovate's `homebrew` manager

You are contributing to the Renovate codebase (renovatebot/renovate). Implement
support for Homebrew formulae whose source is a git repository, not a tarball:

    url "https://gitlab.example.com/group/project.git",
        tag:      "v1.6.2",
        revision: "344cd2ee3463abab4c16ac0f9529a846314932a2"

This must work for GENERIC git hosts (self-hosted GitLab, Forgejo, Gerrit, etc.),
not just one provider. Today the manager only handles tarball URLs and explicitly
skips git URLs.

## Ground yourself FIRST (do not trust prior assumptions, including this prompt's)
1. Read `CONTRIBUTING.md` and any docs under `docs/development/` about adding/
   changing a manager, test coverage rules, and commit conventions.
2. Read the current `lib/modules/manager/homebrew/` in full: `extract.ts`,
   `update.ts`, `utils.ts`, `handlers/`, `types.ts`, `readme.md`, and all
   `*.spec.ts` + fixtures. Map the real handler interface and update flow.
3. Inspect `package.json` scripts to learn the exact lint / type-check / test /
   coverage commands. Use those discovered commands throughout — do not guess.
4. Read the `git-tags`, `github-tags`, and `gitlab-tags` datasource modules to
   confirm their `packageName` / `registryUrls` / digest contracts.

## Design constraints (verify each against the real code before implementing)
- `sha256` is currently mandatory in `extract.ts` and blocks git formulae. Make it
  required ONLY for tarball URLs; git+tag formulae have no sha256.
- Parse `tag:`, `revision:` (and detect `branch:` / `using: :git`) from the formula.
- Host selection:
  - `github.com` -> `github-tags`, packageName `owner/repo`, host in registryUrls
  - `gitlab.com`  -> `gitlab-tags`, packageName project path, host in registryUrls
  - everything else (self-hosted / Gerrit / Forgejo) -> generic `git-tags`, where
    `packageName` is the FULL clone URL and registryUrls is NOT set.
- Map `tag:` -> `currentValue`, `revision:` -> `currentDigest`.
- Update handler rewrites `tag:` and `revision:` IN LOCKSTEP (a new tag with a stale
  revision is a correctness bug). Resolve the new digest via the datasource.
- SCOPE: implement git `tag:` + `revision:` only. Explicitly defer `head do` blocks,
  branch-only, and Subversion/Mercurial `using:` forms. Do not regress any existing
  tarball behavior — all current tests must stay green.

## Definition of done (this is the acceptance bar)
- New extract + update logic with the host-detection above.
- Tests added to the manager's `*.spec.ts` using the repo's fixture pattern, with
  fixtures for: github.com, gitlab.com, a self-hosted host (generic git-tags),
  tag-only, tag+revision, and an unsupported/invalid case. Meet the repo's coverage
  requirement (Renovate enforces full coverage — confirm the exact threshold).
- Manager `readme.md` updated: document git URL support, the host->datasource
  mapping, the no-changelog/auth caveats for generic `git-tags`, and add any newly
  used datasource to the "supported datasources" list.
- Lint, type-check, and the full test suite pass via the discovered commands.
- A conventional-commit message matching the repo's style (e.g. `feat(manager/
  homebrew): ...`).

## Working loop — REPEAT UNTIL >=90% CONFIDENCE
After each implementation pass, run lint + type-check + tests, then self-review
against this rubric and assign a calibrated confidence score (0–100%) that a
Renovate maintainer would accept this as-is:

  [ ] Matches existing homebrew handler/extract/update architecture (not a rewrite)
  [ ] sha256 gating correct; no regression in tarball tests
  [ ] Generic git-tags path correct (packageName = clone URL, no registryUrls)
  [ ] Host-specific paths correct (packageName + registryUrls)
  [ ] tag + revision updated in lockstep; digest resolved, not faked
  [ ] Tests cover all branches incl. error/skipReason paths; coverage threshold met
  [ ] readme.md + datasource list updated and accurate
  [ ] Lint + type-check + tests all green
  [ ] Scope discipline: no head/branch-only/svn/hg sneaking in
  [ ] Commit message follows repo convention
  [ ] Idiomatic with neighboring managers (imports, types, regex helpers, logging)

If confidence < 90%: list the specific failing/weak items, fix them, and loop.
Do NOT stop at the first passing test run. Keep looping until you reach >=90%.

When you reach >=90%: STOP. Do NOT commit, push, or open anything. Present the
completed checklist with item-by-item justification and your confidence score,
then WAIT for my explicit go-ahead before making any commit or PR.

## Report when you pause
1. Final confidence score with per-checkbox justification.
2. A unified diff / file list of every change.
3. Any decisions a maintainer might push back on, with your reasoning.
4. PROCESS NOTE: Renovate gates new-feature PRs on a feature-request discussion
   first. State this explicitly and draft a short discussion post (what/why/how
   Renovate decides when to act) the user can open before submitting the PR.

Our conversation.

---

Is this a feature that we can work on to get implemented? Or has there been any pushback before adding something like this? One thing that will change is that the Homebrew manager needs to accept the Git hash that is not sha256, etc.