Symfony version(s) affected

5.4.x

Description

Hello

The upgrade from Symfony 5.3.x to Symfony 5.4.x led to multiple MappingException in one of my project.

From what I could investigate, I think that this commit could be at the origin of - what I consider being a - BC Break as it changes the default value of mapping type from "annotation" to "attribute" in the following use case.

What I describe below is working properly in Symfony 5.3.x.

How to reproduce

I'm on a legacy project separated into bundles.

One of that bundle provides an embeddable class in an Entity folder.

namespace App\FooBundle\Entity;

/**
 * @ORM\Embeddable
 */
class Foo
{
}

⚠️ It's important to ensure that there's no entity in the App\FooBundle\Entity, only the embeddable.

Then Another bundle contains an entity using that embeddable

namespace App\BarBundle\Entity;

/**
 * @ORM\Entity
 */
class Bar
{
    /**
     * @ORM\Embedded(class="App\FooBundle\Entity\Foo")
     *
     * @var Foo
     */
    protected $foo;
}

and the doctrine configuration is the following:

# config/packages/doctrine.yaml

orm:
    auto_mapping: true
    # "mappings" key is not defined

Possible Solution

The solution I found is to explicitly define the mapping type in doctrine configuration

# config/packages/doctrine.yaml

orm:
  mappings:
    AppFooBundle:
      is_bundle: true
      type: annotation

I don't know if any change has to be done regarding the code itself, maybe it requires an additional row in this part of the upgrade documentation.

Additional Context

No response