Cloning Posts with serialized post meta

hi there,

I was looking at your code to see how you clone/duplicate posts because I wanted to do something similar in my plugin.

I noticed an issue when posts are cloned with serialized post meta, or when the post meta was stored as an array (which is serialized by WP).

By adding a small check when you loop through the meta, it will also handle serialized arrays correctly:

foreach ( $meta as $key => $val ) {
  $meta_value = $val[0];
  if ( is_serialized( $meta_value ) ) {
    $meta_value = @maybe_unserialize( $meta_value );
  }

  update_post_meta( $new_id, $key, $meta_value );
}