I want to use the official coding standard for Joomla! 4 to check my own Joomla! components.

I can't find the official coding standard anywhere for Joomla! 4 (neither the written rules or the phpcs ruleset). I found this github repo but that seems to only be the standard for Joomla! 3. At least it's the not Joomla! 4 standard. Because after running composer install it installs the ruleset to the following directory: libraries/vendor/joomla/cms-coding-standards/lib/Joomla-CMS/ruleset.xml, which is different from the one in the linked repository. So it would seem I found the correct ruleset.xml since it is included in the 4.0-dev branch. But when I try to use this ruleset by running ./libraries/vendor/bin/phpcs libraries/cms --report=checkstyle --extensions=php --encoding=utf-8 -p --standard=./libraries/vendor/joomla/cms-coding-standards/lib/Joomla-CMS. Which is the same configuration as specified in the build.xml. I get the following error:

PHP Fatal error:  Uncaught PHP_CodeSniffer_Exception: Referenced sniff "Joomla.Commenting.FileComment" does not exist in /home/jor/Projects/joomla-cms/libraries/vendor/squizlabs/php_codesniffer/CodeSniffer.php:1167

It seems to me the Joomla! rules are not installed. Which makes sense since the libraries/vendor/joomla/cms-coding-standards/lib/Joomla-CMS/ directory doesn't contain a sniffs directory which is required by phpcs to know how to enforce the rules defined in the ruleset.xml. So how do I use the.

Additionally there in the build.xml there seem to be more tools running checks on the php code:

• PHP_Depend
• PHPMD
• Lint

Trying to use ant to run the build.xml is no luck as i get the same errors and more from other tools. I will spare you the output of that.

If I am missing some official Joomla! documentation where this is defined I am sorry, I did try to find documentation where this is defined.

I do see others working on fixing the codestyle so I assume others have gotten this to work on their local machine rather than see for example this Pull Request #25471

I have 3 questions:

• where is the Joomla!4 codestyle defined?
• how do I use phpcs with the same codestyle standards as the 4.0-dev branch uses?
• Who maintains the codestyle standards for phpcs?

P.S. I'm not sure if i should label this as Feature Request or bug or something else on Github.