https://integration.wikimedia.org/ci/job/php-composer-test/7340/console
00:23:26 + /srv/deployment/integration/composer/vendor/bin/composer test 00:23:27 This version of the Vector skin requires MediaWiki 1.25+... 00:23:27 00:23:27 Time: 484ms; Memory: 15Mb 00:23:27 00:23:27 Finished: SUCCESS
This is because the composer autoloader is including Vector.php, which will die if the wfLoadExtension function does not exist (which it will not outside the context of MediaWiki...).
Right, this was embarrassing.
I spent some time on #composer looking into this and talking to ethanol/alcohol, one of composer's developers.
The issue essentially is that since we put Vector.php into composer.json's autoload field, anything that requires vendor/autoload.php is going to also include Vector.php. Unfortunately, jakub-onderka/php-parallel-lint includes ../../autoload.php and so composer test just die()s. (Not sure if CodeSniffer requires it too.)
I think the easiest and most direct solution is the one ethanol suggested on IRC: check in Vector.php whether it is being executed in a CLI environment, and if it, then don't die. This seems okay because there is no common situation where Vector.php will be included in a CLI environment, except maybe in maintenance/eval.php.
If there's a different approach entirely that might be more suitable, we can discuss that here. In the meantime, I'll submit a patch.
Change 220725 had a related patch set uploaded (by Polybuildr):
Vector.php: Don't die on missing wfLoadSkin if in CLI environment
Change 221183 had a related patch set uploaded (by Paladox):
Don't autoload Vector.php using composer.json