[wp-trac] [WordPress Trac] #31822: Hierarchical custom taxonomy not showing children in admin panel

[WordPress Trac]

#31822: Hierarchical custom taxonomy not showing children in admin panel
--------------------------+------------------------------
 Reporter:  pinkivy       |       Owner:
     Type:  defect (bug)  |      Status:  new
 Priority:  normal        |   Milestone:  Awaiting Review
Component:  Taxonomy      |     Version:  4.1.1
 Severity:  normal        |  Resolution:
 Keywords:                |     Focuses:
--------------------------+------------------------------
Changes (by boonebgorges):

 * component:  General => Taxonomy


Comment:

 > Please skip the lecture on updating the core files and address the issue
 that the cache needs to be flushed in order to get children taxonomy items
 to show in the admin screen.

 No lecture was forthcoming. How can you identify and fix bugs in core
 files if you don't edit the core files?

 I'm not able to reproduce this on my local installations. Can I ask for
 some additional info?

 - You are flushing the object cache and also deleting the
 'academic_program_type_children' option. I assume you've verified that
 both of these are necessary to prevent the incorrect behavior you've
 described? This suggests that the 'academic_program_type_children' option
 is populated with a flat list that contains only top-level items. Have you
 verified that this is the case? Theoretically, this option should only be
 generated from https://core.trac.wordpress.org/browser/tags/4.1.1/src/wp-
 includes/taxonomy.php#L3823, but the `'get' => 'all'` param in that
 function should ensure that the entire tree is fetched.
 - Have you reproduced this with all plugins/mu-plugins disabled? It's
 possible that something is interfering either with `get_terms()` or
 something like that, and polluting the cache somehow.

 If you're able to produce the problem on a completely vanilla installation
 of WP (save, of course, for the code that you're using to register the
 custom taxonomy), please share explicit details on how to reproduce the
 issue. This includes your custom taxonomy code, as well as whatever steps
 you're performing (presumably, creating some terms, publishing posts?,
 visiting edit-tags.php, all in some specific order). Thanks.

--
Ticket URL: <https://core.trac.wordpress.org/ticket/31822#comment:1>
WordPress Trac <https://core.trac.wordpress.org/>
WordPress publishing platform