SF functional test example

FunctionTest.php

public function testSomething(): void
{
    $client = static::createClient();
    
    $entity = self::$container->get('em')->find(…, 1);
    $entity->setState(1);
    self::$container->get('em')->persist($entity);
    self::$container->get('em')->flush();
    
    $client->request(…, …);
    
    $entity->setState(2);
    self::$container->get('em')->persist($entity);
    self::$container->get('em')->persist($entity);
    // Boom
    self::$container->get('em')->flush();
}

• Make sure that self::assertSame($client->getContainer()->get('em'), self::$container->get('em'));
• Avoid $this->em->clear(); in a HTTP request.

@tdomarkas exactly the opposite advice of https://twitter.com/Ocramius/status/1241770426218557441 😄

Just to clarify: avoid $this->em->clear(); in a HTTP request IF you want to introspect and operate on the same entities after $client->request() is over. 🙂

EDIT: But if that can't be done or you don't want to care what happens inside a request, indeed - just refresh the entity.

ServiceResetter during Kernel boot will clear the EM no matter what, so not too much one can do