get_post_class not working properly

Question

I have a plugin on my WordPress site that lists the most visited pages. I recently realized that it was displaying certain pages that I don't want to display. I also want to be able to disable pages of a certain category.

I found this line of code for the actual display of the widget:

public static function list_items( $post, $defaults ) {
        setup_postdata( $post );
        $post_id                = get_the_ID();
        $title                  = get_the_title() ? get_the_title() : $post_id;
        $post_class         = implode(get_post_class());
        $permalink          = get_permalink();
        $pre_thumbnail  = (has_post_thumbnail() && $defaults['thumbnail'] == 'before_title') ? get_the_post_thumbnail(get_the_ID(), $thumbnail_size) : '';
        $post_thumbnail = (has_post_thumbnail() && $defaults['thumbnail'] == 'after_title') ? get_the_post_thumbnail(get_the_ID(), $thumbnail_size) : '';
        $item                       = '
            <li class="' . $post_class . '">
                <a href="' . $permalink . '" title="' . $title . '">
                    ' . $pre_thumbnail . $title . $post_thumbnail . '
                </a>
            </li>
        ';
        $item                       = apply_filters('wp_most_popular_list_item_single', $item, $post_id, $title, $post_class, $permalink);
        echo $item;
    }

While this works, when it displays the classes, they are not spaced properly, so a page that should display: class="post-20 pagetype-page status-publish hentry category-member tag-member" is instead displaying class="post-20pagetype-pagestatus-publishhentrycategory-membertag-member".

Because of this, I cannot target the class category-member using CSS, or any other classes for that matter. How can I fix this?

I've tried removing the implode() from the $post_class array, but that has done nothing. I ave also tried simply using post_class() and get_post_class() to no avail.

Answer 1

An empty string is used for the glue parameter of implode(). get_post_class() will return an array, and you want to separate the array values with a space, so use this:

$post_class = implode( ' ', get_post_class() );

This appears to be a bug in the WP Most Popular plugin. I submitted an issue to the wordpress.org forums here. Hopefully the author will fix the bug, otherwise the fix posted above will be overwritten if the plugin is updated.