WordPress at a glance
function is not described

_clear_modified_cache_on_transition_comment_status() WP 4.7.0

Clear the lastcommentmodified cached value when a comment status is changed.

Deletes the lastcommentmodified cache key when a comment enters or leaves 'approved' status.

This is an internal function for using it by WP core itself. It's not recommended to use this function in your code.

No Hooks.

Return

null. Nothing.

Usage

_clear_modified_cache_on_transition_comment_status( $new_status, $old_status );
$new_status(string) (required)
The new comment status.
$old_status(string) (required)
The old comment status.

Changelog

Since 4.7.0 Introduced.

Code of _clear_modified_cache_on_transition_comment_status() WP 5.7.2

<?php
function _clear_modified_cache_on_transition_comment_status( $new_status, $old_status ) {
	if ( 'approved' === $new_status || 'approved' === $old_status ) {
		foreach ( array( 'server', 'gmt', 'blog' ) as $timezone ) {
			wp_cache_delete( "lastcommentmodified:$timezone", 'timeinfo' );
		}
	}
}