Running scripts/tests in CI for the first time turned up a real defect in the gate
itself, not just in the harness.
`jq -e` over EMPTY input exits 4 on jq >= 1.7 but 0 on jq 1.6 — verified against both
binaries, not inferred. The docs-only pagination guard in
pretooluse-merge-consent.sh leaned on that exit status to reject a transport failure.
On jq 1.6, which the CI runner ships:
page 2 errors -> gq returns empty -> jq guard wrongly PASSES -> n is empty so
[ "$n" -lt 50 ] errors into false -> the loop walks PAST the failed page -> page 3
legitimately returns [] -> files_complete=yes over a PARTIAL list -> the docs-only
exemption fires over unread pages that may be pure code.
That is the very defect the guard's own comment describes, reintroduced one layer down
by a jq version difference. Fixed by rejecting an empty body explicitly rather than
inferring it from jq's exit status. The same hardening is applied to the
review-verdict status read, which fell through to `vstate=""` -> deny (fail-CLOSED, so
never a hole) but would have surfaced the wrong message.
Why it survived: the existing transport-failure test asserts the right thing but can
only observe the bug where jq is 1.6, so it passes on a developer Mac with the bug
fully present — and the suite had never run anywhere else. The new test removes that
dependency by shimming ONLY jq 1.6's empty-input exit status, so it pins the property
on any host. Mutation-verified: revert the fix and it goes red on jq 1.8.2.
The shim is deliberately narrow (no `-n`): a broader first version swallowed the
`jq -n` calls `decide` uses to build its JSON, so the hook emitted nothing and every
decision read as a passthrough — the verifier manufacturing the exemption it was
meant to disprove. test_jq16_shim_actually_reproduces_the_quirk now pins the shim
itself, `-n` case included.
Suite: 113 passed under jq 1.8.2 AND under jq 1.6.
Refs #631