Sending mails does not work

[Guite]

Expected behavior

Sending mails working.

Actual behavior

No mails are sent.

Steps to reproduce

Try at /mailer/config/test.

Reason

The problem relates to delivery_addresses: { } in generated.yml
When this is replaced by delivery_addresses: [] mails are sent correctly.

See also

symfony/symfony#16266
symfony/symfony#9870

[Guite]

There is a fix in symfony/symfony#17578 but this has been merged into Symfony 3.1.
See also: http://symfony.com/blog/new-in-symfony-3-1-customizable-yaml-parsing-and-dumping

[Guite]

Because DynamicConfigDumper extends YamlDumper anyway we can maybe backport the fix from Symfony 3.1 to it.

[craigh]

@Guite - probably we need an upgrade routine to reformat the generated.yml file?

[Guite]

No I don't think this is required. Because earlier the default value was not [], but null:

core/src/system/MailerModule/Form/Handler/ModifyConfigHandler.php

Line 135 in 7fee79e

'delivery_address' => !empty($currentConfig['delivery_address']) ? $currentConfig['delivery_address'] : null,

I checked two installations of 1.4.0 and both files contained delivery_address: null.

Note Symfony changed delivery_address to delivery_addresses in a recent update, so this does not affect earlier core versions 😄