Subcategory archive does work with any name as parent category in URL

[ocean90]

Parent category is parentcategory and his sub category is subcategory.

The URL will be domain.com/category/parentcategory/subcategory.

The problem is, that you will get the same page if you use any words as parentcategory.

Examples:

• domain.com/category/xxx/subcategory
• domain.com/category/subcategory
• domain.com/category/foo/bar/subcategory

IMO redirect_canonical should do his work here (and sometimes it does).

In 3.1 it does redirect.
In 3.1.4 it doesn't redirect; after r17549.
In 3.2.1 it doesn't redirect.
Duck_ found that it does redirect before r18079.
In current trunk it doesn't redirect.

We need tests for all the bugs the have been fixed and unfixed over time.

Related: #17174, #16627, #12659

Some more canonical tests: ​[UT444]

History in trunk

[13091] for original /category/child/ to /category/parent/child/ redirection.

Broken by [15462] as "The easiest one is to assume that if we had come to the right category page without any get variables, we don't need the logic for redirecting to the canonical category page. This is valid statement, because that logic relies only on removing get arguments." (#14201) is incorrect. parse_url($tax_url) ... $redirect['path'] = $tax_url['path']; is redirecting to the correct term link.

Fixed again in [15705], but re-introducing #14201. The scope of the !empty($redirect['query'] conditional was changed.

Re-broken by [18079] which moved stuff back inside !empty($redirect['query'] (also fixing #14201 again).

tl;dr: canonical isn't kicking in unless the URL has a query. This was done as a stop-gap fix for #14201.

Duck_, any idea what we can do here?

Waiting for a fix, i created this hack:

add_action( 'wp', 'baw_non_duplicate_content' );
function baw_non_duplicate_content()
{
	global $wp_query;
	if( isset( $wp_query->query_vars['category_name'], $wp_query->query['category_name'] )
		&& $wp_query->query_vars['category_name'] != $wp_query->query['category_name'] ):

		$correct_url = str_replace( $wp_query->query['category_name'], $wp_query->query_vars['category_name'], $wp->request );
		wp_redirect( home_url( $correct_url ), 301 );
		die();
	endif;
}