When running bin/console event-dispatcher you may pass it an argument to show what event you are interested to see the listeners for. Example:

bin/console event-dispatcher kernel.request
bin/console debug:event-dispatcher "Symfony\Component\Security\Http\Event\CheckPassportEvent"

Since more and more events are using FQCN now, this is a handful to write. Other questions that I face is, should I use single backslash \ or double \\?

This PR propose that you can use a pattern as second argument. If there is no exact match, it will search for similar event names. Say:

bin/console debug:event-dispatcher CheckPassportEvent
bin/console debug:event-dispatcher checkpassport
bin/console debug:event-dispatcher Security
bin/console debug:event-dispatcher Security
bin/console debug:event-dispatcher App

#SymfonyHackday