In I0c92d40744, I tried to use the new hook registration system from T240307: Hook container with strong types and DI. It seems to work at runtime, but CI complains (console):
13:25:19 There was 1 failure: 13:25:19 13:25:19 1) ExtensionJsonValidationTest::testPassesValidation with data set #48 ('/workspace/src/extensions/Wik...p.json') 13:25:19 Failed asserting that '/workspace/src/extensions/Wikibase/client/../extension-client-wip.json did not pass validation.\n 13:25:19 [] The property HookHandlers is not defined and the definition does not allow additional properties\n 13:25:19 ' is false. 13:25:19 13:25:19 /workspace/src/tests/phpunit/structure/ExtensionJsonValidationTest.php:64 13:25:19 /workspace/src/maintenance/doMaintenance.php:105
Are we not supposed to use HookHandlers yet? Is this too bleeding-edge? :D