On a repo with no entity types defined for some reason our list of empty entity types ends up being null instead of an array.
This goes against the phpdoc so should be fixed.
#0 /srv/mediawiki/php-master/extensions/Wikibase/repo/includes/Specials/SpecialEntitiesWithoutPageFactory.php(31): NO_FUNCTION_GIVEN() #1 /srv/mediawiki/php-master/extensions/Wikibase/repo/includes/Specials/SpecialEntitiesWithoutPageFactory.php(35): Wikibase\Repo\Specials\SpecialEntitiesWithoutPageFactory::newFromGlobalState() #2 /srv/mediawiki/php-master/includes/specialpage/SpecialPageFactory.php(393): Wikibase\Repo\Specials\SpecialEntitiesWithoutPageFactory::newSpecialEntitiesWithoutLabel() #3 /srv/mediawiki/php-master/includes/specialpage/SpecialPageFactory.php(426): MediaWiki\Special\SpecialPageFactory->getPage(string) #4 /srv/mediawiki/php-master/includes/specials/SpecialSpecialpages.php(56): MediaWiki\Special\SpecialPageFactory->getUsablePages(User) #5 /srv/mediawiki/php-master/includes/specials/SpecialSpecialpages.php(44): SpecialSpecialpages->getPageGroups() #6 /srv/mediawiki/php-master/includes/specialpage/SpecialPage.php(569): SpecialSpecialpages->execute(NULL) #7 /srv/mediawiki/php-master/includes/specialpage/SpecialPageFactory.php(558): SpecialPage->run(NULL) #8 /srv/mediawiki/php-master/includes/MediaWiki.php(288): MediaWiki\Special\SpecialPageFactory->executePath(Title, RequestContext) #9 /srv/mediawiki/php-master/includes/MediaWiki.php(862): MediaWiki->performRequest() #10 /srv/mediawiki/php-master/includes/MediaWiki.php(517): MediaWiki->main() #11 /srv/mediawiki/php-master/index.php(42): MediaWiki->run() #12 /srv/mediawiki/w/index.php(3): include(string) #13 {main}
Reproduction https://commons.wikimedia.beta.wmflabs.org/wiki/Special:SpecialPages