Unexpected slugs for same-title different-parents term creation

[dd32]

When creating a new term which matches an existing terms name, it uses that slugs slug as the slug prefix, which can result in an unexpected term slug.

For example, take this:

Foo (slug: foo)
 - Bar  (slug: foo-bar)

If we now create a root level "Bar" term, it'll get a slug of foo-bar-2, when one would expect it to receive bar since no conflicting slug exists.

This is related directly to [28733] / #17689.

Unit test attached showing behaviour.

[dd32]

Looks like this has been kind of touched on in https://core.trac.wordpress.org/ticket/30780#comment:15

[tyxla]

In wp_insert_term() when initially figuring out a slug, make sure that existing term is considered only on the current term level.

[tyxla]

It appears that when determining the slug (when not specifically provided) in wp_insert_term(), if there is a term with the same name on any level, the slug of that term is used. This can be clearly seen at [28733] - lines 2441:2442. The issue can be resolved if a term with the same name is considered only when it is on the current term level. Attached a patch for that - 31270.patch.

[snakefoot]

This would also resolve #5034, which I have been waiting for :-). Would love to upgrade from WP2.0 to WP4.2 :-)

[boonebgorges]

Yes, this is pretty much the same issue as #5034. 31270.patch​ looks good at a glance, but a change like this will need the support of a number of unit tests. I think we have some tests currently that describe the existing behavior, and those will have to be carefully reviewed and updated as necessary; new tests may have to be written for various combinations of same/different taxonomy, hierarchical/non-hierarchical taxonomy, same/different/no parent.

[snakefoot]

When looking at the trunk code for wp_insert_term(), then it already has a check with is_taxonomy_hierarchical() that verify combinations of slug+term within the same parent. Together with the protection of wp_unique_term_slug() (concat of parent-term with child-slug).

[snakefoot]

There is an issue with the query-parser, when having two similar slugs with different parents. The query-parser doesn't include the parent hierarchy when generating the SQL, and just picks a "random" slug.

I have attached a plugin to #5034, which implements a hack, but it would be nicer if the query-parser handled it.

Instead of a bug, then it is a feature just like #5034 :)

[DrewAPicture]

31270.patch​ needs a refresh and still needs unit tests to move forward. Punting.