Need to write EmailExtension(DI) SYmfony3 correctly, what's wrong with my code?

Question

symfony

Actually, you need to write 2 services on a symbol, one takes the swiftmailer to the constructor and sends letters through it, the second is the controller, which also takes this service to the constructor via DI and sends letters using it. My code: ideone.com/QDAWRf

Answer 1

23 line.
You are instantiating ContainerBuilderinstead of using the one passed as a function parameterload