M2M property is empty in preDelete of BeanPersistAdapter

[Wosch96]

We have a BeanPersistAdapter with a preDelete method. The BeanPersistAdapter is registered for class "A", which has a M2M relation to class "B" with CascadeType.REMOVE. Now "A" references four objects of "B".

Expected behavior

The preDelete() method of the "A"BeanPersistAdapter should contain a list with four objects of "B".

Actual behavior

The List is empty.

Steps to reproduce

I also tested this with the ebean test models (MnyB and MnyC):

1. Create a MnyBPersistAdapter.

public class MnyBBeanPersistAdapter extends BeanPersistAdapter {
  @Override
  public boolean isRegisterFor(Class<?> cls) {
    return MnyB.class.isAssignableFrom(cls);
  }

  @Override
  public boolean preDelete(BeanPersistRequest<?> request) {
    if (((MnyB) request.bean()).getCs().isEmpty()) {
      System.out.println("MnyB contains zero elements of MnyC.");
    } else {
      System.out.println("MnyB contains elements of MnyC.");
    }
    return true;
  }
}

Create a MnyB object and add a MnyC object to the M2M reference.

  @Test
  public void test() {
    MnyB mnyB = new MnyB();
    MnyC mnyC = new MnyC();
    mnyB.getCs().add(mnyC);
    DB.save(mnyC);
    DB.save(mnyB);

   MnyB mnyBFromDB = DB.find(MnyB.class, mnyB.getId());
    // The preDelete of the BeanPersistAdapter should contain one object of MnyC.
    assertThat(mnyBFromDB).extracting("cs").isEqualTo(List.of(mnyC));

    DB.delete(mnyBFromDB);
  }

The test runs green and the console shows the following output:

 MnyB contains zero elements of MnyC.

Tell me if I'm wrong, but I think that the list of MnyC reference objects should not already be emptied in the PreDelete().
I am looking forward to your opinion.

Thanks,
Wosch