cleanup-branches

name	cleanup-branches
description	Plan and (only after user confirmation) delete remote and matching local git branches whose PR is already merged or closed (not merged) and that have no remaining commits or file changes. Use when the user asks to clean up, prune, or delete merged/closed branches (브랜치 정리, cleanup branches, delete merged branches).

Cleanup branches

Delete remote branches whose PR is already merged or closed (not merged) and that have no leftover commits or file changes. Delete matching local branches too. Never delete main or dev.

Plan first. Show what would be deleted; delete only after the user explicitly asks to delete.

Rules

Delete only when all are true; otherwise skip and say why:

1. Branch is not main or dev (local or origin/*)
2. Not the currently checked-out branch
3. No open PR for that head (gh pr list --head <branch> --state open)
4. A merged or closed PR exists for that head:
   • prefer merged: gh pr list --head <branch> --state merged
   • else closed (not merged): gh pr list --head <branch> --state closed
5. Tip has no commits beyond that PR tip: git merge-base --is-ancestor <tip> <prHeadRefOid> (prefer origin/<branch> tip; squash/rebase → do not require ancestry on dev/main)
6. Local delete: if a worktree has the branch checked out, that tree is clean (status --porcelain empty); dirty → skip local only

Never force-push or rewrite history. Use git branch -D only after the PR checks (plain -d often fails after squash).

Workflow

1. git fetch --prune origin
2. Candidates: remote heads under origin (exclude main/dev/HEAD), plus local-only branches with the same checks
3. Plan (default): report would-delete vs skipped. Do not run git push --delete or git branch -D.
4. Stop and wait. Delete only when the user explicitly asks to delete.
5. Delete (after confirmation only): safe remote → git push origin --delete <branch>; matching safe local → git branch -D <branch>; report removed vs skipped.

Would delete:
- origin/<branch> — merged PR #<n>
- origin/<branch> — closed PR #<n> (not merged)
- <branch> (local) — matched origin / merged PR #<n>

Skipped:
- <branch> — <reason>

After confirmation, use the same shape with Removed: instead of Would delete:.