LSP violation example in PHP / Laravel

gistfile1.php

<?php

interface MenuItemInterface {
    public function setTitle($title);
    public function getTitle();
    public function setUrl($url);
    public function getUrl();
}

class RouteBasedMenuItem implements MenuItemInterface {

    protected $title;
    protected $routeName;
    
    public function __construct($title, $routeName) {
        $this->title = $title;
        $this->routeName = $routeName;
    }
    
    public function setTitle($title) {
        $this->title = $title;
    }
    
    public function getTitle() {
        return $this->title;
    }
    
    public function setUrl($url) {
        throw new \BadMethodCallException('
            The URL of this menu item cannot be set directly; Use setRouteName() instead!
        ');
    }    
    
    public function getUrl() {
        return \Url::route($this->routeName);
    }
    
    public function setRouteName($routeName) {
        $this->routeName = $routeName;
    }
    
    public function getRouteName() {
        return $this->routeName;
    }
    
}