The post-commit hook passes `git diff --name-only HEAD~1 HEAD` as
changed_paths to `_rebuild_code`. That list includes deletions, and
`_rebuild_code` correctly identifies them (lines 352-367 in watch.py)
and evicts the stale nodes from the preserved set. The rebuilt graph
is intentionally smaller.
`_check_shrink` then refuses to overwrite the existing graph.json
because it only sees the node-count delta, not the cause. The guard
fires with "Refusing to overwrite — you may be missing chunk files
from a previous session. Pass --force to override."
Result: every commit that deletes a tracked file silently leaves stale
nodes in graph.json. The user must either pass --force (which also
disables the guard for legitimate failure modes) or manually re-run
`graphify update . --force` after delete-heavy commits.
Fix: thread a `had_explicit_deletions` flag from `_rebuild_code` into
`_check_shrink`. When the caller has declared the deletions, the
smaller graph is the expected outcome and the guard is skipped. The
guard remains intact for SILENT shrinkage — its actual purpose —
from failed semantic chunks or corrupted runs.
The fix is opt-in by design: callers that don't pass `changed_paths`
(e.g. the post-checkout full rebuild path) keep the old conservative
behavior. Only paths that explicitly track deletions get the bypass.
Tests added (tests/test_watch.py):
- `test_check_shrink_blocks_silent_shrink` — pre-existing behavior intact
- `test_check_shrink_allows_force_override` — pre-existing behavior intact
- `test_check_shrink_allows_explicit_deletions` — new: deletion bypass
- `test_check_shrink_allows_no_existing_data` — first-run case
- `test_check_shrink_allows_growth` — sanity
- `test_check_shrink_unlinks_tmp_on_refuse` — cleanup on refusal
- `test_check_shrink_keeps_tmp_when_deletions_declared` — no spurious unlink
- `test_rebuild_code_prunes_deleted_file_nodes` — end-to-end probe of the
exact scenario the post-commit hook triggers (git init, build, delete
one file, re-run with the deleted path in changed_paths, verify the
graph shrinks and the surviving file's nodes are preserved)
All 8 new tests pass; full test_watch.py + test_build.py + test_export.py
(74 tests) pass with no regressions.
mohamadkattan12
6fba4e4594