Excluding post type from WordPress link builder

I have created a custom post type with parameter ‘public’ set to true. This is because I have to have it accessible in plugins that help you to build queries for post display, such as the Views (part of Toolset) plugin.

On the other hand, when I create a new post or page and use the link builder I don’t want entries of this post type to show up in the search box there. Is there any way to achieve this aim?

Versions <= 3.6.1

It looks like the function wp_link_query() is used to display the internal posts/pages when you press the Or link to existing content in the “link builder”:

wp_link_query() is defined in /wp-includes/class-wp-editor.php.

It is queried via the wp_ajax_wp_link_ajax(), defined in the file /wp-admin/includes/ajax-actions.php.

These functions don’t have any explicit filters to change the query.

Version 3.7 (?)

It looks like there are patches on the way introducing the filter wp_link_query_args

You can check it out here:

http://core.trac.wordpress.org/ticket/18042

The milestone is set as 3.7, so this might be your lucky version 😉

If that’s the case, then you might probably fix this with:

Example 1:

If you want to list the custom post types by hand:

/**
 * Filter the link query arguments to change the post types. 
 *
 * @param array $query An array of WP_Query arguments. 
 * @return array $query
 */
function my_custom_link_query( $query ){

    // change the post types by hand:
    $query['post_type'] = array( 'post', 'pages' );  // Edit this to your needs

    return $query; 
}

add_filter( 'wp_link_query_args', 'my_custom_link_query' );

Example 2:

If you only want to eliminate a single custom post type, but keep all the others, then you can try:

/**
 * Filter the link query arguments to change the post types. 
 *
 * @param array $query An array of WP_Query arguments. 
 * @return array $query
 */
function my_custom_link_query( $query ){

    // custom post type slug to be removed
    $cpt_to_remove="news";      // Edit this to your needs

    // find the corresponding array key
    $key = array_search( $cpt_to_remove, $query['post_type'] ); 

    // remove the array item
    if( $key )
        unset( $query['post_type'][$key] );

    return $query; 
}

add_filter( 'wp_link_query_args', 'my_custom_link_query' );

where I used the demo slug 'news'.