Why is a old comment reply comment appearing at end of comment list as well

Question

EDIT: Updated function to use get_comments offset param. Issue is still occurring.

I am displaying 5 comments at the end of an article and using ajax to request the rest of the comments. On this page, http://www.universityaffairs.ca/opinion/in-my-opinion/phd-studies-in-canada-a-dilemma-for-international-students/#comments

the comment by Joshan Rodrigues is a reply to another comment. This is fine.

When I load the rest of the comments through ajax by clicking the More Comments link, Joshan Rodrigues' comment appears again at the end of the list, even if the comment date is older. Give it a try.

Below is function called by ajax.

function get_more_comments() {
global $wpdb; // this is how you get access to the database

$comments = get_comments( 
                array(
                    'post_id'   => $_REQUEST['post_id'],
                    'status'    => 'approve',
                    'order'     => 'ASC',
                    'offset'    => 5,
                    'number'    => 1000
                )
            );

echo '<ol class="commentlist">';
wp_list_comments( 
            array(
                'avatar_size' => 0,
                'walker'    => new Walker_Comment_custom(),
            ),
            $comments
        );
echo '</ol>';

die(); 
}

Any idea why this is happening?

Answer 1

I think that a good way to get what you are trying to do is to use comment__not_in argument of get_comments() function. Send the IDs of the comments currently being displayed in the Ajax request and use them in the comment__not_in argument. For example, you could send those IDs as comment__not_in[] query var (array format):

$comment_not_in = $_REQUEST['comment__not_in'];
$comments = get_comments( 
                array(
                    'post_id'         => $_REQUEST['post_id'],
                    'status'          => 'approve',
                    'order'           => 'ASC',
                    'comment__not_in' =>  $comment_not_in,
                    'number'          => 1000
                )
            );

Also, I recommend to sanitize the data. As IDs are expected to be integer numbers we can do something like this:

$comment_not_in = array_map( 'intval', $_REQUEST['comment__not_in'] );
$comments = get_comments( 
                array(
                    'post_id'         => (int) $_REQUEST['post_id'],
                    'status'          => 'approve',
                    'order'           => 'ASC',
                    'comment__not_in' =>  $comment_not_in,
                    'number'          => 1000
                )
            );