With MediaWiki and a MySQL database, when I run the PHPUnit group Database one of the parser test fails mysteriously:
1) ParserIntegrationTest::testParse with data set "parserTests.txt: Namespace takes precedence over interwiki link (T53680)" ('[details omitted]') Failed asserting that two strings are equal. --- Expected +++ Actual @@ @@ -'<p><a href="/wiki/MemoryAlpha:AlphaTest" title="MemoryAlpha:AlphaTest">MemoryAlpha:AlphaTest</a> +'<p><a href="/wiki/Special:Badtitle/NS100:AlphaTest" title=":AlphaTest">MemoryAlpha:AlphaTest</a> </p>'
I haven't looked into it, it seems a namespace MemoryAlpha / id 100 is not properly initialized. The debug log has:
Title::getNsText: Unknown namespace ID: 100 Title::getNsText: Unknown namespace ID: 100 Title::getNsText: Unknown namespace ID: 100
Reproduction
php phpunit.php --debug-tests --filter '(ParserMethodsTest::testValidCovers|T53680)'