Two docs tests located this delivery's CHANGELOG section by the literal
heading `## Unreleased` (one also required it to be the first section).
The release commit renames it to `## v6.4.0 — <date> — <title>`
(docs/release-runbook.md § 1.4), so all 16 content pins failed on the
release commit while the content was the same.
One shared helper, tests/helpers/changelog-section.mjs, now finds the
section by its title under either heading, wherever it stands (a later
delivery's section above it does not move the pins), with a trailing \r or
spaces tolerated, and only when it stands exactly once. Every content
assertion is unchanged; their messages no longer say "Unreleased". New
tests pin the accepted headings and seven near misses (version, date,
title, the literal dot in 1.9), and the helper on a later section, a \r,
a duplicate and a missing section.
Measured: 46/46 pass against main's CHANGELOG and against the release
commit's CHANGELOG; before the change, 16 failed on the release commit.
Three mutants of the helper (a looser date, no escaping, no trim) are
each failed by one test.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
