Uniqueness is a property of HEAD alone — no base ref, no merge base, no base
blob. It sat downstream of all three, so every degradation path returned
success on a tree carrying a duplicate.
The base-blob path was the worst: a branch that introduces CHANGELOG.md hit a
bare `exit 0` on a message that was true about deletion and silent about the
duplicate in front of it. STRICT could not reach it — STRICT guards the two
skip() calls, and that is not one of them.
That inverted the two halves. Deletion needs a diff to see; duplication is the
one changelog_section() actually mis-renders, stopping at the second heading
and truncating the release's real body. The half with the live extraction bug
behind it had the most ways to silently not run.
Moved, not rewritten. The skip messages now say containment skipped and that
uniqueness already passed. The CI step is no longer pull_request-only, with a
`github.ref_name` fallback because base_ref is empty on a push and a bare
`origin/` under STRICT would redden every push to main. The script is also now
100755, matching cast's copy of the same file.
Regression cases pin the ORDER, not the exit code: verified they go red
against the pre-fix script (7 failures) and green against the fixed one.
Same defect fixed upstream in heavy-duty/box#144 (heavy-duty/box#143), which
rig's copy of this script was ported from. Found by claude-bot-andresmgsl and
codex-bot-andresmgsl reviewing #99.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The arming rule (#66) guards ONE heading — does the top section agree with
VERSION? — and is silent about the rest of the file. The failure that lives
there is an author adding an entry under `## Unreleased` who replaces the
shipped heading below it instead of inserting above it. git merges the
one-line edit cleanly, `changelog_armed()` stays green (correctly: the top
section is still right), and the shipped release loses its section entirely.
It surfaces a whole release later, when release.yml refuses to publish a
section `changelog_section()` can no longer find by heading.
"A heading disappeared" is a property of a DIFF, not of a tree, so this is
its own script rather than a clause in the arming check — which is also
driven from test/release.sh against constructed non-git VERSION + CHANGELOG
pairs that could not express it. The rule needs no tuning: release headings
are append-only, so SUPERSET is exact, and the ceremony's stamp passes by
construction because `Unreleased` fails the version shape.
Ported from heavy-duty/box#122, with box's second half intact: containment
cannot catch a DUPLICATED heading, since the duplicate is head-side surplus
and `comm -23` is blind to extras there — so uniqueness on HEAD is asserted
alongside it. rig's symptom differs from box's and the comments say so:
box's extractor re-arms on every `## ` line and ABSORBS what sits between
the copies, while rig's `changelog_section()` has `if (found) exit` and
TRUNCATES at the second copy, dropping the release's real body.
Wired on pull requests only (on a push to main the merge base is HEAD, so
the assert is vacuous), with CHANGELOG_MONOTONIC_STRICT=1 and fetch-depth: 0
so a checkout that cannot reach the base ref fails rather than skipping
quietly forever.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
