<?php
 namespace MauticPlugin\VocativeBundle;
 
 use Mautic\PluginBundle\Bundle\PluginBundleBase;
 
 class VocativeBundle extends PluginBundleBase
 {
 
 }

Try that in your IDE without the PluginBundleBase class available. Pain in the %body_part%.

By fetching this skeleton to your code, the problem is solved. Your IDE will finally get access to all those classes you are inheriting from.

• composer require-dev friendsofmautic/bundle-skeleton
• copy & paste whole MauticBundleSkeleton under name of your bundle name to a place you want
• replace in the copied MauticBundleSkeleton the Skeleton word in every place by your bundle name
• get inspired by EventListener\WhyMeSubscriber and remove it, or rewrite

If any error happens, check the logs for what happened.

1. they are placed in app/logs dir in your Mautic, like /var/www/mautic/app/logs/mautic_prod-2016-02-19.php for example
2. or, if they are more fatal or just Mautic does not catch them (error 500), see your web-server logs, like /var/log/apache2/error.log

This library provides Mautic code by composer (packagist.org respectively),

If you are going to create a Mautic plugin for Twig, a good start can be mautic-twig-plugin-skeleton.