Use fully qualified names in inline code

[dingo-d]

This PR depends on #98. Once that is merged, this PR should be rebased to the master branch.

The PR adds rules about the fully qualified names in the inline code and is the continuation of the additions of 'modern' PHP code in the WordPress PHP Coding Standards handbook based on the make post by Juliette Reinders Folmer.

[jrfnl]

I'm not sure this needs to be added to the manual. As of PHP 8.0, using whitespace or comments within the name is a parse error (remember: the Make post was written well before PHP 8.0 was released).

[dingo-d]

I'm not sure this needs to be added to the manual. As of PHP 8.0, using whitespace or comments within the name is a parse error (remember: the Make post was written well before PHP 8.0 was released).

I can add it as a note below, would be a good addition IMO 👍🏼

[jrfnl]

While the note about PHP 8.0 does help, I still don't think this section needs to be in the manual.

Code shouldn't cause parse errors on any of the supported PHP versions, Doesn't matter the reason of the parse error.

That's not something which is a coding standard, that's something which is a basic necessity for the code to be able to run.

[dingo-d]

Oh, you meant we should drop this all together? I just added all the rules we had in the spreadsheet 😂

But your reasoning makes complete sense. I'll close this PR 👍🏼

[jrfnl]

Yes, sorry if my original remark wasn't clear enough.

[GaryJones]

Was there any proposal about when to use inline FQCN vs an import?

[jrfnl]

There was not. At the time, we decided that as WP isn't using namespaces/import use statements, it was not up to WP to set a guideline/standard for when to use FCNs vs import statements.

I know of at least one company in the WP sphere where they strictly enforce always importing classes, but forbid importing global functions/constants and instead enforce using FQNs for those. For namespaced functions/constants, the namespace is imported, and the functions/constants use partially qualified names.

Both Slevomat as well as PHPCSExtra have various sniffs which could enforce one or the other, so userland has a choice here (and the means to enforce their choice).