In a trait, relative namespaces with @Flow\Import don't work

[neos-bot]

Jira issue originally created by user cognifloyd:

Given the following trait (as a random example of a trait that includes an imported property):

namespace Some\Package;
use TYPO3\Flow\Package\PackageManagerInterface;
trait FancyTrait {
  /****
   * @Flow\Import
   * @var PackageManagerInterface
   */
   $packageManager;
}

The following does not work:

namespace Some\Package;
use FancyTrait;
class SomeClass {
  use FancyTrait;
}

Uncaught Exception: TYPO3\Flow\Core\Booting\Exception\SubProcessException

Message

  Uncaught Exception: TYPO3\Flow\Object\Exception\UnknownObjectException

  Message
    The object "PackageManagerInterface" which was specified as a property
  in
    the object configuration of object
    "Some\Package\SomeClass"
    (automatically registered class) does not exist. Check for spelling
    mistakes and if that dependency is correctly configured.

  More Information
    Exception code 1265213849
    File          
  Packages/Framework/TYPO3.Flow/Classes/TYPO3/Flow/Object/DependencyInjection/ProxyClassBuilder.php
  line 538
    Reference code 20141231173308a299ca


More Information
  Exception code 1355480641
  File           Packages/Framework/TYPO3.Flow/Classes/TYPO3/Flow/Core/Booting/Scripts.php line 528
  Reference code 201412311733073dade3

To get around the issue, I have to use anything used in the trait in the class that uses the trait. That means that the following does not trigger the same error:

namespace Some\Package;
use FancyTrait;
use TYPO3\Flow\Package\PackageManagerInterface;
class SomeClass {
  use FancyTrait;
}

So, Flow needs to be able to look in traits while compiling. It is really ugly to import things that the file is not using, and PhpStorm helpfully offers to remove those unused references, so it's easy to end up with a broken system since Flow is not taking traits into account.

Jira-URL: https://jira.neos.io/browse/FLOW-170

[neos-bot]

Comment created by @bwaidelich:

FYI: That one is probably related to https://forge.typo3.org/issues/46008 and https://forge.typo3.org/issues/50909 (and maybe can be fixed in a similar manner)