This is MediaWiki version 1.21alpha.

Running test pre-save transform: comment containing math... PASSED
Running test BUG 1887, part 2: A <math> with a thumbnail- math enabled... No lock manager defined with the name `nullLockManager`.
Backtrace:
#0 /srv/mediawiki/includes/filebackend/FileBackend.php(111): LockManagerGroup->get('nullLockManager')
#1 /srv/mediawiki/includes/filebackend/FileBackendStore.php(59): FileBackend->__construct(Array)
#2 /srv/mediawiki/includes/filebackend/FSFileBackend.php(61): FileBackendStore->__construct(Array)
#3 /srv/mediawiki/extensions/Math/MathTexvc.php(238): FSFileBackend->__construct(Array)
#4 /srv/mediawiki/extensions/Math/MathTexvc.php(47): MathTexvc->getBackend()
#5 /srv/mediawiki/extensions/Math/MathTexvc.php(204): MathTexvc->getHashPath()
#6 /srv/mediawiki/extensions/Math/MathTexvc.php(33): MathTexvc->callTexvc()
#7 /srv/mediawiki/extensions/Math/Math.hooks.php(54): MathTexvc->render()
#8 [internal function]: MathHooks::mathTagHook('2+2', Array, Object(Parser), Object(PPFrame_DOM))
#9 /srv/mediawiki/includes/parser/Parser.php(3848): call_user_func_array(Array, Array)
#10 /srv/mediawiki/includes/parser/Preprocessor_DOM.php(1145): Parser->extensionSubstitution(Array, Object(PPFrame_DOM))
#11 /srv/mediawiki/includes/parser/Parser.php(3071): PPFrame_DOM->expand(Object(PPNode_DOM), 0)
#12 /srv/mediawiki/includes/parser/Parser.php(1149): Parser->replaceVariables('[[Image:foobar....')
#13 /srv/mediawiki/includes/parser/Parser.php(384): Parser->internalParse('[[Image:foobar....')
#14 /srv/mediawiki/tests/parser/parserTest.inc(489): Parser->parse('[[Image:foobar....', Object(Title), Object(ParserOptions), true, true, 1337)
#15 /srv/mediawiki/tests/parser/parserTest.inc(403): ParserTest->runTest('BUG 1887, part ...', '[[Image:foobar....', '<div class="thu...', 'math', '')
#16 /srv/mediawiki/tests/parser/parserTest.inc(385): ParserTest->runTests(Object(TestFileIterator))
#17 /srv/mediawiki/tests/parserTests.php(91): ParserTest->runTestsFromFiles(Array)
#18 {main}