wp_title spits warnings and returns a blank when a query is both is_post_type_archive and is_category/is_tax/etc

[devesine]

When a query is made against both a post type and a category / taxonomy / et cetera, the query is both is_category and is_post_type_archive. The queried_object is set to the first object type it comes to; category / taxonomy come before post_type, so the queried_object is a term here.

wp_title walks through each is_ option in turn and resets the title with every one it finds being true. When there is both a category and a post type archive, single_term_title gets called first, successfully setting the title, but then post_type_archive_title is called, which assumes the queried_object is in fact a post type object; it spits out a couple of warnings and returns a blank title.

Probably, since its subordinate title functions depend on the queried_object being as expected, wp_title should use else if rather than just if (in the same way that get_queried_object does), but I'm not sure if that would have implications elsewhere.

(Tested against trunk r21768 as well as 3.4.1)

Attached is a unit test that demonstrates the problem.

[SergeyBiryukov]

Related/duplicate: #18614, #19035, #20994

[johnstonphilip]

More info on this problem: ​http://wordpress.stackexchange.com/questions/71157/undefined-property-stdclasslabels-in-general-template-php-post-type-archive

[lkraav]

Yeap, hitting this in 3.5.2

[wonderboymusic]

This got fixed at some point