XWIKI-20437: Wrong order of categories in space administration

[Sereza7]

Jira URL

https://jira.xwiki.org/browse/XWIKI-20437

Changes

Description

• Split the code of the findCustomSectionsToConfigure macro to make it a bit more readable/reusable.
• Made a second lookup to get all the categories in all the cases, so that we always get all the order information.
• The structures used are complexe for velocity, so deep copying was needed at some point.
• The $query initialization was unnecessary on modern XS.
• Added comments to explain a bit more the process.

Clarifications

• TLDR: To get the right order, we need to retrieve the ordering information scattered across multiple objects that are all throughout the wiki.
• Despite the amount of changes in this PR, there is barely any DOM change.
• It was a pain to debug. AFAIK we don't have ways to make deep copies in Velocity so I had to have a few lines of hard-coded deep copy.
• It's a patch on this legacy system. Ideally we'd replace and deprecate it whole, but I hope the comments and structure added in here help make this less of a pain to replace without a hitch in the future. E.g. use a value property on categories (the standard way, the one already used for sections in categories) instead of a linkedlist simili-structure to compute a score.
• I created a few utility macros (non API) to avoid getting a 200 lines macro ^^'
• Technically this makes local administration pages slower. I did not measure the impact on performance though.

Screenshots & Video

After the PR was applied on my local instance, it looked like:

Executed Tests

Manual tests (see screenshots above).
Docker tests for admin are really slow, so far though they did not fail (WIP).

Expected merging strategy

• Prefers squash: Yes
• Backport on branches:
  • None. This is too dangerous for LTS IMO.

[mflorea]

Suggested change

	#foreach ($entry in $adminMenu)
	#set ($entryCopy = {})
	#set ($discard = $entryCopy.putAll($entry))
	#set ($entryChildrenCopy = [])
	#set ($discard = $entryChildrenCopy.addAll($entry.children))
	#set ($discard = $entryCopy.put('children',$entryChildrenCopy))
	#set ($discard = $outputList.add($entryCopy))
	#end
	#set ($discard = $outputList.addAll($jsontool.fromString($jsontool.serialize($adminMenu))))

This should work because we're using only Map, List and simple types (string, number, boolean) to build the administration menu.

[Sereza7]

Thank you! That looks way better than what I had :)
Addressed in 24ee46e 👍