WordPress Version: 5.9
/**
* Determines whether a post type is considered "viewable".
*
* For built-in post types such as posts and pages, the 'public' value will be evaluated.
* For all others, the 'publicly_queryable' value will be used.
*
* @since 4.4.0
* @since 4.5.0 Added the ability to pass a post type name in addition to object.
* @since 4.6.0 Converted the `$post_type` parameter to accept a `WP_Post_Type` object.
* @since 5.9.0 Added `is_post_type_viewable` hook to filter the result.
*
* @param string|WP_Post_Type $post_type Post type name or object.
* @return bool Whether the post type should be considered viewable.
*/
function is_post_type_viewable($post_type)
{
if (is_scalar($post_type)) {
$post_type = get_post_type_object($post_type);
if (!$post_type) {
return false;
}
}
if (!is_object($post_type)) {
return false;
}
$is_viewable = $post_type->publicly_queryable || $post_type->_builtin && $post_type->public;
/**
* Filters whether a post type is considered "viewable".
*
* The returned filtered value must be a boolean type to ensure
* `is_post_type_viewable()` only returns a boolean. This strictness
* is by design to maintain backwards-compatibility and guard against
* potential type errors in PHP 8.1+. Non-boolean values (even falsey
* and truthy values) will result in the function returning false.
*
* @since 5.9.0
*
* @param bool $is_viewable Whether the post type is "viewable" (strict type).
* @param WP_Post_Type $post_type Post type object.
*/
return true === apply_filters('is_post_type_viewable', $is_viewable, $post_type);
}