Add Gerrit forge adapter

[abhinavgautam01]

Summary

Adds initial Gerrit support as a forge adapter.

This maps Gerrit projects, branches, tags, files, and changes into the existing forge interfaces where they fit cleanly. Unsupported Gerrit concepts explicitly return ErrNotSupported.

Closes #12.

What works

• Adds gerrit forge type and detection via /config/server/version
• Adds Gerrit REST client with XSSI prefix stripping
• Supports repositories/projects
• Supports branch list/create/delete
• Supports tag listing
• Supports file content retrieval
• Maps Gerrit changes to pull requests for get/list/diff/comment/submit/abandon/restore
• Supports reviewer request/removal and review submission
• Adds explicit unsupported-service stubs for issues, labels, milestones, releases, CI, secrets, deploy keys, notifications, collaborators and commit statuses
• Updates CLI help, config docs, README and token lookup

Tests

• go test ./...
• git diff --check

[mestadler]

+1 on this feature, fills the single gap that I have for the cli tool, will run a qa on it against my gerrit and provide feedback.

[andrew]

Thanks for this, the adapter is well structured and follows the existing gitea/gitlab shape closely. Tests pass locally and pr checkout will work for Gerrit changes for free since #117 already handles refs/-prefixed head refs.

A few things to address before merging, see inline. The main ones are the Code-Review label type, the hardcoded abandon/restore messages, and the gerrit-review.googlesource.com default which doesn't actually work with the auth scheme implemented here.

[andrew]

Thanks for the quick turnaround. Labels, abandon/restore/submit bodies, PathUnescape and the intString cleanup all look good.

Two things from the follow-up commit:

Dropping case "gerrit" from defaultDomainForType means it now falls through to github.com — resolve_test.go and repo_test.go even assert {"gerrit", "github.com"}. That's worse than the googlesource default; forge --type gerrit ... without a host will quietly hit github. Return "" for gerrit and have the callers error when the domain is empty.

The HTMLURL change in convertProject went to the wrong spot. /admin/repos/<encoded> was the correct repo page; the comment was about BlobURL building on top of it. I'd revert HTMLURL to /admin/repos/... and have BlobURL just return repoHTMLURL (no good file-browse URL without gitiles).

[abhinavgautam01]

thanks for catching those,

I've reverted the HTMLURL logic back to using the /admin/repos/ endpoint and updated BlobURL to just return the repoHTMLURL . I also fixed the domain resolution so that defaultDomainForType explicitly returns an empty string for gerrit , causing the CLI to correctly error out when a domain isn't provided rather than quietly defaulting to github.com.

the test assertions have been updated to reflect this behavior too.