Doctrine relation from MappedSuperClass to Entity - symfony

Question

I want to ultimately have an abstract base class that defines a relationship to another entity for all inheriting Entity-classes. So have this test-setup that was created with symfony's make:entity-command.
The only thing I changed was switching the MappedSuperClass's property-visibility from private to protected to make them visible to the extenders.
This is the MappedSuperClass:
[...]
/**
* Class TestMappedSuperclass
*
* #package App\Entity
* #ORM\MappedSuperclass()
*/
class TestMappedSuperclass
{
/**
* #ORM\Id
* #ORM\GeneratedValue
* #ORM\Column(type="integer")
*/
protected $id;
/**
* #ORM\OneToMany(targetEntity=TestTarget::class, mappedBy="testMappedSuperclass")
*/
protected $targets;
public function __construct()
{
$this->targets = new ArrayCollection();
}
//..getters/setters,add/remove...
}
This my target-entity for the mapping:
[...]
/**
* #ORM\Entity(repositoryClass=TestTargetRepository::class)
*/
class TestTarget
{
/**
* #ORM\Id
* #ORM\GeneratedValue
* #ORM\Column(type="integer")
*/
private $id;
/**
* #ORM\ManyToOne(targetEntity=TestMappedSuperclass::class, inversedBy="targets")
*/
private $testMappedSuperclass;
// ..getters,setters..
}
This is the extending entity class:
[...]
/**
* #ORM\Entity(repositoryClass=TestEntityRepository::class)
*/
class TestEntity extends TestMappedSuperclass
{
}
So when I try to do a make:migration it produces the following error:
Column name `id` referenced for relation from App\Entity\TestTarget towards
App\Entity\TestMappedSuperclass does not exist.
Using: Symfony 5.1, Doctrine 2.7

Answer 1

AFAIK you need to have repeat id as protected in TestEntity :
/**
* #ORM\Entity(repositoryClass=TestEntityRepository::class)
*/
class TestEntity extends TestMappedSuperclass
{
/**
*
* #ORM\Column(name="id", type="integer")
* #ORM\Id
* #ORM\GeneratedValue(strategy="AUTO")
*/
protected $id;
}
I took this from a project where i´m using mappedSuperClass like this, i´m not relate entities in it though