[WordPress] Custom Post Type Pagination

00-pre-get-posts.php

<?php

use WP_Query;

add_action('pre_get_posts', __NAMESPACE__ . '\\customPostTypePagination');
/**
 * If we're on the 'acme-post-type' page, then adjusts pagination so there are only two posts per page. This will 
 * affect pagination so we can use built-in pagination links to easily page through the content.
 *
 * @param WP_Query the instance of the query object that contains information to populate the template.
 *
 * @return WP_Query an unmodified version of the query object or a modified version if we're on the acme post-type.
 */
function customPostTypePagination(WP_Query $query)
{
  if (isset($query->query['post_type']) && 'acme-post-type' == $query->query['post_type']) {
    $query->set('posts_per_page', 2);
  }
}