Category tree should be an acyclic graph (Community Wishlist/W281)

Description

Currently, many categories contain themselves. See en:User:SDZeroBot/Category cycles for a full list (about 3000 cycles). per en:WP:Categorization#Category tree organization, the category tree should resemble a directed acyclic graph as far as possible.

Solution 1:

The best way to solve this problem would be to enforce that categories do not contain themselves. This could be opt-in for certain categories to reduce conflict. You could have a template or hidden category like "acyclic category" that when applied to a given category enforces that it's children will not contain it.

Solution 2:

At the very least, a method for detecting cycles should be present and ideally if a category is in a cycle it should show that to the user so that people can fix it.

(Note: I tried submitting this request before but it seems to have failed as I cannot find it anywhere)

Assigned focus area

Unassigned

Type of wish

Feature request