A new test for missing image files referenced from CSS I'm adding in https://gerrit.wikimedia.org/r/#/c/235903/ exposed an issue in MobileFrontend:
b@ubuntu15:/var/www/wiki/tests/phpunit$ php phpunit.php structure/ResourcesTest.php PHPUnit already present PHPUnit 3.7.37 by Sebastian Bergmann. Configuration read from /var/www/html/w/tests/phpunit/suite.xml ............................................................. 61 / 1847 ( 3%) ............................................................. 122 / 1847 ( 6%) ............................................................. 183 / 1847 ( 9%) ............................................................. 244 / 1847 ( 13%) ............................................................. 305 / 1847 ( 16%) ............................................................. 366 / 1847 ( 19%) ............................................................. 427 / 1847 ( 23%) ..........................FF................................. 488 / 1847 ( 26%) ............................................................. 549 / 1847 ( 29%) ............................................................. 610 / 1847 ( 33%) ............................................................. 671 / 1847 ( 36%) ............................................................. 732 / 1847 ( 39%) ............................................................. 793 / 1847 ( 42%) ............................................................. 854 / 1847 ( 46%) ............................................................. 915 / 1847 ( 49%) ............................................................. 976 / 1847 ( 52%) ............................................................. 1037 / 1847 ( 56%) ............................................................. 1098 / 1847 ( 59%) ............................................................. 1159 / 1847 ( 62%) ............................................................. 1220 / 1847 ( 66%) ............................................................. 1281 / 1847 ( 69%) ............................................................. 1342 / 1847 ( 72%) ........................FF................................... 1403 / 1847 ( 75%) ............................................................. 1464 / 1847 ( 79%) ............................................................. 1525 / 1847 ( 82%) ............................................................. 1586 / 1847 ( 85%) ............................................................. 1647 / 1847 ( 89%) ............................................................. 1708 / 1847 ( 92%) ............................................................. 1769 / 1847 ( 95%) ............................................................. 1830 / 1847 ( 99%) ................. Time: 32.96 seconds, Memory: 42.50Mb There were 4 failures: <snip> 3) ResourcesTest::testFileExistence with data set #1366 ('/var/www/html/w/extensions/MobileFrontend/resources/mobile.pag esummary.styles/noimage.png', 'mobile.pagesummary.styles', '/var/www/html/w/extensions/MobileFrontend/resources/mobile.p agesummary.styles/noimage.png') File '/var/www/html/w/extensions/MobileFrontend/resources/mobile.pagesummary.styles/noimage.png' referenced by 'mobile.p agesummary.styles' must exist. Failed asserting that file "/var/www/html/w/extensions/MobileFrontend/resources/mobile.pagesummary.styles/noimage.png" e xists. /var/www/html/w/tests/phpunit/structure/ResourcesTest.php:24 /var/www/html/w/tests/phpunit/MediaWikiTestCase.php:131 <snip> FAILURES! Tests: 1847, Assertions: 5901, Failures: 4.
(This is only visible if you fix T111516 first.)
The "noimage" looks confusing, but there is indeed a "noimage.svg" file in that directory that is missing a "noimage.png" counterpart, while the styles use both. noimage.png was separated from its brother in d1f1d1b74ef1f270c78b62c29367dcf1993e825b and deleted in 9c0456c7aa891d629cd8d766c037017a585f8a88.