Referencing same object multiple times before flushing

[lavoiesl]

Copied from doctrine/DoctrineFixturesBundle#57 by @deeky666

I just encountered a problem with referencing an object multiple times with different names before flushing. It seems only the first reference I make gets persisted and is available in following fixtures. Here is an example:

public function load(ObjectManager $manager)
{
        $obj = new Obj();
        $obj->setFoo('bar');

        $manager->persist($obj);

        $this->addReference('first-reference', $obj);
        $this->addReference('second-reference', $obj);

        $manager->flush();
}

When referencing "first-reference" in the following fixture I get the persisted object I expect. But if I reference "second-reference" I get an object that is in an unpersisted state. This is problematic if I want to relate the previously persisted object to another object in a following fixture by referencing "second-reference".

If I flush before adding the references, everything works fine. Is it a bug or an intended behaviour?