A stub that prints nothing makes `size=$(du -sk x)` empty, so every
`((size > 0))` is false and the trace walks past every guarded branch.
Two such traces compare identical while exercising none of the changed
code -- a green check that proves nothing, which is the exact failure
mode this harness exists to prevent.
--stub now takes `name=output`. Measured on a fixture whose `sudo rm -rf`
is guarded by a size test: the silent stub gives `size=[]` / "branch
skipped" and never records the rm; `--stub 'du=4096\t/some/dir'` gives
`size=[4096]` / "BRANCH TAKEN" and captures it.
This weakens the earlier disk_cleanup_check.sh trace, which used a silent
du stub: that trace only proved the empty-size path identical. The real
run from /tmp is what covered the populated path. Noted in the evidence.
Docs also record two limits found while surveying: file-placement
installers are not yet traceable (stub cp/chmod/ln and the trace is
empty; don't and it rewrites the live system), and baselines for scripts
reading relative paths must run from the script's own directory.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011w2Pj4Ek3ZNMQVYcFHgXDY
Adding it to the handoff pushed that file to 280 lines -- the handoff is
not exempt from the cap it exists to enforce. The usage, the two caveats
(stubs always exit 0; unstubbed binaries run for real) and the proof it
catches both bug classes now live in docs/shell-split-verification.md,
which is the file dedicated to exactly this. The handoff keeps a pointer.
Also dropped the per-directory count table, which carried a "do not work
from this table" warning and went stale every session, and compressed the
co-agent narrative to the diagnostic commands worth keeping. 280 -> 246.
Recorded there too: the harness needs no main(), which matters because
none of the remaining near-miss shell targets have one, so
verify_shell_split.sh cannot check any of them.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011w2Pj4Ek3ZNMQVYcFHgXDY
The prettier hook is pre-push only, so this only surfaced when the push
ran. Two list-continuation lines rewrapped.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011w2Pj4Ek3ZNMQVYcFHgXDY
Three new sections, each earned this session:
- A --skip-install flag is not evidence a script is safe to run.
shell_check.sh gates only the pacman branch on it; the AUR branch runs
regardless, and a "baseline" run installed four packages before I
killed it. Grep the flag's variable and read every hit first.
- A stubbed run cannot reach a bug in a seam that passes state. It
sources the libs and never calls them. analyze_repo.sh passed bash -n,
shellcheck, both diffs and the stub, and still aborted at runtime --
set -e turning a function's last conditional into its return value,
and a self-referencing nameref warning into the script's own output.
- Do not make a clean file shfmt-dirty, and re-count comment banners
after shfmt -w, which deletes ones it thinks are stray.
Adding them pushed the doc to 285, so it is split: recipes.md keeps how
to make a split (231), the new verification.md holds how to find out it
is wrong (70). The recipe doc now points at it from the stubbed-run
bullet, where someone about to trust the stub will actually read it.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011w2Pj4Ek3ZNMQVYcFHgXDY
