Why flush is necesary on methods like grabFromRepository?

Inizia da src/Codeception/Module/Doctrine2.php intorno al flush referenziato in grabEntitiesFromRepository, quindi segui le chiamate da tests/_support/Base/BaseActor.php alle righe 193, 164 e 405–423. Riproduci la configurazione del test funzionale e verifica quando la transazione diventa rollback-only; il lavoro è completato quando viene identificato se il flush del modulo causa il commit failure e la causa confermata viene documentata o corretta.

I have configured Doctrine2 and Symfony modules as follow:

modules:
    enabled:
        - Symfony:
              app_path: 'src'
              environment: 'test'
        - Doctrine2:
              depends: Symfony
              cleanup: true

and I have created a helper to be used as part of my Functional tests as follow (snippet with relevant parts only):

public function grabWorkableEntityForCase(int $schemeID = CcType::VISA, ?int $cId = null): Cases
{
    /** @var Cases $caseEntity */
    $caseEntity = $this->grabEntityFromRepository(Cases::class, [
        'ccType' => $schemeID, 
        (new Criteria())->orderBy(['id' => Criteria::DESC])->setMaxResults(1)
    ]);
    
    // If we need an specific Case just override the previous value
    if (null !== $cId) {
        $caseEntity = $this->grabEntityFromRepository(Cases::class, ['id' => $cId]);
    }
    
    // Unlock it
    $caseEntity->removeLock();
    
    //Grab dispute cycle RFI
    $disputeCycle = $this->grabEntityFromRepository(DisputeCycle::class, ['id' => DisputeCycle::RETRIEVAL]);
    $functionalCode = $this->grabEntityFromRepository(FunctionCode::class, [
        'disputeCycle' => $disputeCycle, 
        (new Criteria())->orderBy(['id' => Criteria::DESC])->setMaxResults(1)
    ]);
    
    // And assigned to a worker if need be otherwise use always a random user
    if (null !== $userID) {
        $user = $this->grabEntityFromRepository(User::class, ['id' => $userID]);
    } else {
        $user = $this->grabWorkableUserEntity();
    }
    
    $caseEntity->setUser($user);
    
    $this->haveInRepository($caseEntity);
    
    return $caseEntity;
}

from my test the code above is being called as:

public function _before(FunctionalTester $I)
{
    $this->user = $I->grabWorkableUserEntity();
    $this->case = $I->grabWorkableEntityForCase();
    $I->flushAllTables(false, $this->case->getId());
}

But I end up with the following error:

1) WriteOffOutcomeFunctionalCest: Will record and send fee collection
 Test  tests/functional/FullWriteOffOutcomeFunctionalCest.php:willRecordAndSendFeeCollection

  [Doctrine\DBAL\ConnectionException] Transaction commit failed because the transaction has been marked for rollback only.

Scenario Steps:

 15. $I->grabEntityFromRepository("App\Entity\DisputeCycle",{"id":1}) at tests/_support/Base/BaseActor.php:193
 14. $I->grabEntityFromRepository("App\Entity\Cases",{"ccType":1,"0":"Doctrine\\Common\\Collections\\Criteria"}) at tests/_support/Base/BaseActor.php:164
 13. $I->emptyTable("App\Entity\StatusHist",38613) at tests/_support/Base/BaseActor.php:405
 12. $I->emptyTable("App\Entity\ProcessingOutcome",38613) at tests/_support/Base/BaseActor.php:387
 11. $I->emptyTable("App\Entity\DisputeResponse",38613) at tests/_support/Base/BaseActor.php:396
 10. $I->emptyTable("App\Entity\EventsHistory",38613) at tests/_support/Base/BaseActor.php:423

from the error above lines 193 is:

$disputeCycle = $this->grabEntityFromRepository(DisputeCycle::class, ['id' => DisputeCycle::RETRIEVAL]);

I am not sure if the flush inside grabEntitiesFromRepository method is what is causing this or what could be the reason of it, true story is that I have been trying to debug this for hours without success so any help is more than welcome. What I am a missing here?