wp_nav_menu fallback_cb argument ignored with using menu argument

[jonkirkman]

wp_nav_menu ignores the fallback_cb argument when also using the menu argument.

If this is the expected behavior, it should be documented as it isn't intuitive.

This fails to honor the fallback_cb -

wp_nav_menu(array('menu' => 'mymenu', 'container' => 'false', 'fallback_cb' => ''));

This works as expected -

wp_nav_menu(array('theme_location' => 'mylocation', 'container' => 'false', 'fallback_cb' => ''));

Replying to jonkirkman:

If this is the expected behavior, it should be documented as it isn't intuitive.

It is documented in the PHPDoc for wp_nav_menu. Is there somewhere else that it isn't documented correctly? (​Codex has it, too.)

fallback_cb - If the menu doesn't exists [sic], a callback function will fire. Defaults to 'wp_page_menu'. Set to false for no fallback.

To elaborate, because you're specifying the menu, the only time the fallback_cb would apply is if that menu doesn't exist. In contrast, when you don't specify the menu, until one is assigned to that location the fallback_cb does apply.