The sweep the §12 work called for, run over every test reading a static repo
document. Enumerated population: four such guards (method-spec, ingest-spec,
README, pyproject). Three were already sound — the two spec guards were
anchored in sessions 14/15, and the README guard extracts flags by regex and
cross-checks them against real --help output with explicit vacuity guards.
The fourth was green-but-dead, and it was MEASURED, not inferred:
`assert _PIN in _PYPROJECT.read_text()` stayed GREEN (4 passed) while the real
dependency drifted to >=0.2.110 below the guard's own verified floor, because
the literal survived in a trailing comment. The comment above it claimed
"Detach-proof: the pin and this guard cannot drift apart silently" — the exact
drift it named is what it let through.
Three narrowings, each one a measured degeneration rather than a precaution:
- ANCHOR: match inside the `dependencies = [...]` array, fail-closed with
ValueError when the array is renamed (a silently empty slice would make
every assertion vacuous).
- QUOTED FORM: the slice alone still did not detach — a comment sits inside
the array too. Requiring `"<pin>"` with comments stripped does.
- VALUE BINDING: _PIN is now DERIVED from _VERIFIED_FLOOR/_CEILING via
_pin_for(), so the range this guard enforces and the pin it demands cannot
part company. The error message derives from it too, instead of carrying a
third hand-maintained copy that could lie.
Five permanent red-proofs replace the manual spot-check, all run against a
mutated COPY of the text, never pyproject.toml itself. Measured degeneracy:
substring-anywhere restored -> 1 red; anchor widened to the whole file -> 2
red; the derived-pin binding severed -> 2 red.
Suite 683 -> 688; ruff, format and mypy clean.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FcKMxznPVR9zfdsdu5Ztdn
Kjell Tore Guttormsen
769687159f