1. `date.fromisoformat` is not a YYYY-MM-DD validator. On Python >= 3.11 it also
accepts ISO basic format ("20270101") and week dates ("2027-W01-1"), so a
malformed-looking value passed the blocking check — and which forms parse
depends on the interpreter, meaning the same corpus could validate differently
on a dev machine and on the runner (pr-checks.yml pins only python-version
'3.x'). Knock-on: the catalog's Review-due section sorts on the raw STRING, so
an accepted "20270101" sorted AFTER "2027-01-15" ('-' < '0'), contradicting the
section's own "sorted soonest-first" text. Gate on ^\d{4}-\d{2}-\d{2}$ first,
which fixes both — a fixed-width zero-padded form makes string sort == date sort.
2. A present-but-empty `stale-after:` was collapsed to None by `or None` in the
parser and then skipped by a truthiness guard in the validator, so it passed as
"absent" — a field that silently never fires, which is the exact failure mode
the blocking check exists to prevent. Keep "" distinct from None and test with
`is not None`.
3. `test_catalog_is_date_independent` was partly vacuous: with no date in either
render, both sides were trivially equal after the .replace(). It did still catch
an injected clock-derived marker, but it passed with the feature deleted. Assert
the dates are present.
4. The malformed-date check ran only over the active set, exempting archive
records. Staleness is moot there, but a typo is still a typo — check both wings.
Adds regression tests for each, plus a Review-due row for a topic-file record
(pinning the `../decisions.md` vs bare-filename link forms).
timothy
75139bbf31