Running git clean inside a worktree treats files committed on the feature
branch as untracked — from the worktree's perspective they were never staged.
The executor deletes them, then commits only its own deliverables; when the
worktree branch merges back the deletions land on the main branch, destroying
prior-wave work (documented across 8 incidents, including commit c6f4753
"Wave 2 executor incorrectly ran git-clean on the worktree").
- Add <destructive_git_prohibition> block to gsd-executor.md explaining
exactly why git clean is unsafe in worktree context and what to use instead
- Add regression tests (bug-2075-worktree-deletion-safeguards.test.cjs)
covering Failure Mode B (git clean prohibition), Failure Mode A
(worktree_branch_check presence audit across all worktree-spawning
workflows), and both defense-in-depth deletion checks from #1977
Failure Mode A and defense-in-depth checks (post-commit --diff-filter=D in
gsd-executor.md, pre-merge --diff-filter=D in execute-phase.md) were already
implemented — tests confirm they remain in place.
Fixes#2075
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
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