getNewsletterFromQueue() has too many conditions under which it returns null. Therefore we can not rely on that method when we wont to delete running tasks with no associated newsletter.
[MAILPOET-4708]
When no corresponding newsletter was found the task can be deleted. The behavior
before meant that such a task would remain forever in the database with the
status 'running'.
[MAILPOET-4699]
It was also necessary to add an if condition to check the type of a
variable before calling one of the methods of one of the documented
properties.
[MAILPOET-4363]
In the process it was necessary to change the signature of the method
\MailPoet\Mailer\MetaInfo::getNewsletterMetaInfo() to accept a
SubscriberEntity instead of a Subscriber model and also change
\MailPoet\Cron\Workers\SendingQueue\SendingQueue::processQueue() as it
calls getNewsletterMetaInfo().
Doing this was straightforward, but changing the test class for
SendingQueue was a bit more involved. In particular, the test
SendingQueueTest::testItEnforcesExecutionLimitsAfterQueueProcessing().
This test is a bit brittle and was creating Subscriber models without
saving them to the database with invalid statuses and sources. Switching
getNewsletterMetaInfo() to use entities, while
SendingQueue::processQueue() still uses models, meant that it was
necessary to save the subscribers to the database. Because of this, it
was not possible anymore to use invalid statuses and sources, and
thus, the test changed a bit.
[MAILPOET-4379]
PHPStan reported an error in PHP8.1. When we use
the annotation ReturnTypeWillChange it caused another error
for PHPStan in combination in PHP7.2. The new annotations
are solving those issues.
[MAILPOET-4053]
