Flarum\Core\Discussion::setLastPost PHP Method

    public function setLastPost(Post $post)
    {
        $this->last_time = $post->time;
        $this->last_user_id = $post->user_id;
        $this->last_post_id = $post->id;
        $this->last_post_number = $post->number;
        return $this;
    }