Fixing check for swiftmailer in EmailSenderListener

[mklewitz]

When sending emails by injecting \Swift_Mailer and using the memory spool, no mails are sent out. There are no visible errors and mails are shown as correctly spooled in the profiler. However, the mails are never sent.

That is because the check for $container->has('mailer') in EmailSenderListener is always false at least with swiftmailer-bundle 3.5.2 on symfony 2.5.2. Additionally checking for 'swiftmailer.mailer.default' fixes the issue.

[fabpot]

Can you check on a recent version of Symfony? 3.5 is very old and not maintained anymore.

[mklewitz]

Actually I'm using the newest stable releases. 3.5.2 is the version of swiftmailer-bundle. And the 2.5.2 should've been 5.2.5. Sorry for the typo.

[mklewitz]

To make the problem clearer:
When I inject ContainerInterface as $container this is what happens:

var_dump($container->has('mailer'));
var_dump($container->has('swiftmailer.mailer'));
var_dump($container->has('swiftmailer.mailer.default'));

results in:

bool(false) bool(false) bool(true)

However, bin/console debug:container results in:

  mailer                                                                               alias for "mailer.mailer"
  swiftmailer.mailer                                                                   alias for "swiftmailer.mailer.default"
  swiftmailer.mailer.default                                                           Swift_Mailer

[marphi]

I would like to confirm that issue.

When we added to our project (based on symfony 4.4.26) symfony/mailer, mailer alias has been pointed to Symfony\Component\Mailer\Mailer and has been inlined. Execution of $this->container->has('mailer') has been return false.

So as a result of that memory spool has been stop sending emails.
This PR fixes the memory spool.

[fabpot]

Thank you @mklewitz.