Rule override for each directory (feature request)

[top-master]

Taking just one rule-set XML file from the command line (or something) is really not enough to cover our entire project, its unit test dir specific rules, its sub-module related rules, and so on; all this in a single XML file can get quite complex.

For example, when git add . command is executed it handles current and all sub-directories and:

• It searches for .gitignore files in each directory (starting from the nearest root directory which contains the .git directory until currently being handled directory).
• When .gitignore exists its rules get added to the rule-stack, and once that directory is finished those rules are removed again from the rule-stack (it is using "Last In, First Out" queue or something).

I would like PHPCS to handle the .phpcs.xml files in a similar way, I mean:

• PHPCS should find its root directory by searching in current and parent directories for the nearest composer.json file, which's rule-set is not set to "<use-parent>" (The <use-parent> rule-set should be a reserved keyword to allow sub-modules to reuse the settings from a parent directory, which might be the main project).
• Then PHPCS should get its initial rule-set from that composer.json file (and ignore .phpcs.xml files of any parent directories).
• At last, like git does for .gitignore files, PHPCS should search for .phpcs.xml files in each directory (starting from the root directory, until currently being handled directory).
• When .phpcs.xml exists its rules should get added to the rule-stack, and once that directory is finished those rules should get removed from the rule-stack again.
• Once all this is done, each directory can have its own rules without need to change parent directories rules, and users only need to execute the phpcs . or phpcbf . command (for backward compatibility, when no composer.json file in current-path contains the initial rule-set, PHPCS should just do as it does currently).

[westonruter]

I believe this is the same issue as is being described in the JetBrains issue tracker (for PhpStorm): https://youtrack.jetbrains.com/issue/WI-36028

My use case is that I have a project (a WordPress site) which contains multiple subprojects (WordPress themes and plugins), each of which may have their own configurations for PHPCS, ESLint, etc. When editing a JS file in a subproject, the IDEA lints the file according to the nearest ESLint config in that file's directory tree. In order to get the same behavior with PHPCS, as noted by @MaXal:

So to support this properly we have to change the working directory for each file but that, in turn, will break a lot of configurations since they depend on the working directory being the project root so I suggest filing the feature request to PHPCS to add an option or change the default behavior inline with JSHint (it looks more than reasonable to me).

[jrfnl]

Just want to leave a note here that the workflow as described above presumes a Composer based project, while PHPCS is not limited to Composer supported projects.

[anomiex]

In #3378 I took the approach of pushing the logic for finding the actual configs into the filter, so that people who want to try out things like looking for a composer.json can do that. I took a different approach in my own filter's implementation.

3378 doesn't actually implement the feature requested here in PHPCS's own filters, it just lays the groundwork.