Hide books, vocabularies from settings form if modules are not enabled.

Seems like I might have accidentally stumbled across this and filed 🐛 A "Book name" plugin shows in config when book module not installed; WSOD if you check it Active ... @smustgrave do you have any insight?

(I'm cleaning up old issues as part of a big review of open issues for 🌱 [Plan] Stable 8.x-2.0 release Active : thank you for your patience with me)

No worries. Off a quick glance definitely seems like could be related. Think when I posted that patch it was the first time I had used book before. But may want to come up with a generic solution in case other contrib modules tie in?

Also book is being removed from core in D11.

Copying parts of the issue summary from 🐛 A "Book name" plugin shows in config when book module not installed; WSOD if you check it Active , so I can mark it as a duplicate of this one.

@smustgrave, may I trouble you to add some tests to the merge request?

I just did some manual testing, and i see that if the book module is uninstalled, a disabled "Book name" item shows in the plugin list; but if the taxonomy module is uninstalled, there is no corresponding Vocabulary item (I called these items "placeholders" in the screenshot below but that's not the best name). I've attached a screenshot of a site with BOTH the book, and the taxonomy modules uninstalled (2024-03-03--sitemap--issue-3150052--commit-9351649.png).

I think I'd prefer it if there was no "Book name" item (i.e.: I'd prefer it if the book plugin did what the vocabulary plugin does)... but to some extent what's already in the patch/merge-request is good enough for a 8.x-2.0 release (we can always make it consistent in 8.x-2.1, etc.).

I would like tests before merging this in, however.

(if you don't have the capacity, I can try to write tests myself, but I have a lot on my plate right now)

So may patch was more of a temporary hack then anything. Think some kind of different solution needs to be in place to make sure we either don't load plugins with missing dependencies or if we do how to check that dependencies are missing.

May involve a new key being needed for the sitemap plugins

@smustgrave

I am not sure is it right. I have enabled the book module but the plugin is not visible in sitemap config page