Symfony Entity id is null in Unit Test - php

Question

Hi I have a question i have a script that has this
public function add(Request $request): UserResponse
{
$user = new User();
/** #var $request UserRequest */
$user->setName($request->getName());
$user->setEmail($request->getEmail());
$this->dataService->addUpdate($user);
return new UserResponse(
$user->getId(),
$user->getName(),
$user->getEmail()
);
}
Now I want to Unit Test this function, but it gives me the error that $user->getId() is null instead of an int (the UserResponse() want the first parameter to be int and not null)
But of course when I make a new User() object in my Unit Test it has no ID in it, that is set by the EntityManager (by for me, magic)
I already tried to do something with
$reflectionClass = new ReflectionClass(get_class($user));
$idProperty = $reflectionClass->getProperty('id');
$idProperty->setAccessible(true);
$idProperty->setValue($user, 1);
But this will not help, anyone knows how to fix this error:
1) App\Tests\Service\UserServiceTest::addTest
Expectation failed for method name is equal to 'addUpdate' when invoked 1 time(s)
Parameter 0 for invocation App\Service\DataService::addUpdate(App\Entity\User Object (...)): void does not match expected value.
Failed asserting that two objects are equal.
--- Expected
+++ Actual
## ##
App\Entity\User Object (
- 'id' => 1
+ 'id' => null
'name' => 'test'
'identifier' => null
'email' => 'test#test.nl'

Answer 1

The id from your Entity will only be automatically generated id if you persit and flush.
public function add(Request $request, EntityManagerInterface $em): UserResponse
{
$user = new User();
/** #var $request UserRequest */
$user->setName($request->getName());
$user->setEmail($request->getEmail());
$em->persist($user);
$em->flush();
dd($user->getId);
}