[random test failure] Drupal\FunctionalTests\Bootstrap\UncaughtExceptionTest::testLostDatabaseConnection

The assertion is too specific. testLostDatabaseConnection sets invalid credentials and expects DatabaseAccessDeniedException on the page, which the driver only throws for connect error 1045. Any other connection failure throws a different exception, so the string isn't there and the test fails — that's the reported signature, and why case 'mysql' is currently commented out with a @todo pointing here.

Same shape as #3521851 (there the real error was [1524] Plugin 'mysql_native_password' is not loaded).

Couldn't reproduce as-is locally (MariaDB via PDO always returns 1045 for bad creds), but forcing a non-access-denied failure reproduces it: a bad host shows DatabaseConnectionRefusedException + SQLSTATE[HY000] [2002] and the old assert fails with The text "DatabaseAccessDeniedException" was not found....

So instead of pinning one driver exception, assert what the test cares about — the site 500s with the generic kernel panic and the failure is logged. That holds for every driver and code, so I re-enabled mysql and dropped the @todo. Log anchor is Database::openConnection (every driver throws from it) rather than a class name that varies or SQLSTATE (which mysqli isn't).

testLostDatabaseConnection is green on every driver (MariaDB/MySQL PDO, mysqli, PostgreSQL; skipped on SQLite). The red matrix jobs are unrelated and pre-existing — GdToolkit* rotate tests off by 1px and the EmphasisTest JS flake (#2829040) — not this test.

Also since the comment did read like AI I wanted to just lightly mention this https://www.drupal.org/docs/develop/issues/issue-procedures-and-etiquett...

No issue with AI but it does need to be disclosed.

Thanks, and fair. I do use AI to help draft my comments and code, noting that here. I run and verify everything locally before pushing. For this one I reproduced the failure and ran the test green on MariaDB and SQLite, plus phpcs. Will disclose going forward.

Perfectly fine to do that :)