The queue note named the wrong reason the isnull filter was dead

[rubenvdlinde]

The Queue page's note said assignee_isnull=true fails because SearchQueryHandler::cleanQuery compares the value with === true.

That is a real defect in that method, and it is not why the filter was dead.

cleanQuery() has no production callers at all. What normalises a suffixed parameter is buildSearchQuery()'s underscore-to-nested reconstruction, and isnull was missing from MagicSearchHandler::COMPARISON_OPERATORS — so the filter contributed no condition rather than an inverted one.

Measured over HTTP: both _isnull=true and _isnull=false returned 0 rows. That is the tell. An inverted operator would have answered correctly for one of them.

Fixed in openregister isnull-filter-operator. The IS NULL sentinel stays here because it also works on instances that do not yet carry that change.

No behaviour change

The filter itself was, and remains, correct. Verified on a live instance seeded to be discriminating: 9 cases, 3 assigned, 2 closed, queue = 4.

Documentation only.

[github-actions]

Quality Report — ConductionNL/dossiq @ 37ddc1e

Check	PHP	Vue	Security	License	Tests
lint	✅
phpcs	✅
phpmd	✅
psalm	✅
phpstan	✅
phpmetrics	✅
eslint		✅
stylelint		✅
build		✅
check-manifest		✅
check-vue3-compile		✅
test-l10n		❌
format		✅
check-schema-l10n		✅
check-l10n-js		✅
composer			✅	✅ 106/106
npm			✅	✅ 540/540
app:check-code	⏭️
info.xml	✅
REUSE	❌
PHPUnit					✅
Newman					⏭️
Playwright					⏭️ deferred — runs on the promotion into beta/main, not on a pull request into development
Hydra gates					✅

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Quality workflow — 2026-09-04 09:00 UTC

Download the full PDF report from the workflow artifacts.