Ignore non-nullable typed property for Embeddable when hydrating

[sneakyvv]

This is the PR requested for issue #8014.

Following the explanation in the bug report, when you have a null value in the database (which is valid because the parent property containing the Embeddable can be null, i.e. all the properties o f the Embeddable are null in the database), but the typed property is required (does not allow null), the hydrator should skip setting that null value to the typed property.

[SenseException]

@doctrine/doctrinecore Should this PR target the 2.7 branch?

[alcaeus]

Since 2.6 is no longer maintained, this indeed needs to target 2.7.

[sneakyvv]

target updated

PS: the CONTRIBUTING.md needs updating :-)

I am submitting a bugfix for a stable release
Your PR should target the lowest active stable branch (2.6).

[SenseException]

target updated

PS: the CONTRIBUTING.md needs updating :-)

Thank you. I guess we could change the link to the documentation page where the supported versions are listed and remove versions from the CONTRIBUTING.md.

[beberlei]

This is the wrong bugfix. The problem is that $foo->bar is created, even though its saved as NULL.

If you add the following to line 36, it already fails:

$this->assertNull($foo->bar);

The fix should be that this is already NULL. But thats actually hard to detect, because if all embeddable properities are null, should the embeddable be null? or is the embeddable present?

[beberlei]

Maybe we can even use this, but its actually necessary to check this before line 89:

if ($value === null) {
    return
}

[sneakyvv]

@beberlei I totally agree, and think the embeddable should be null, if all embeddable properties are null. But that's not the current behaviour. The current behaviour it to have the embeddable present (with all null values).
That's what I said in the bug report (#8014)

PS: Kinda related to #4568, because when all properties of the Embeddable are null, the parent property should also be null (which I fix now post-hydrating), but that occurs even later obviously, after all properties of the Embeddable are set.

Since #4568 ended rather badly... I decided to fix that myself like this with a PostLoad-listener:

<?php

namespace App\Infrastructure\Persistence\Doctrine;

use Doctrine\ORM\Event\LifecycleEventArgs;
use Doctrine\ORM\Mapping\ClassMetadata;
use Doctrine\ORM\Mapping\ReflectionEmbeddedProperty;
use Doctrine\Persistence\ObjectManager;

class NullableEmbeddableFixer
{
    private ObjectManager $objectManager;

    public function postLoad(LifecycleEventArgs $eventArgs)
    {
        $this->objectManager = $eventArgs->getObjectManager();

        $this->fixNullEmbeddables($eventArgs->getObject());
    }

    private function fixNullEmbeddables($object, \ReflectionProperty $parentProperty = null, $parentObject = null)
    {
        $hasNonNullProperties = false;
        /** @var ClassMetadata $embeddedMetadata */
        $embeddedMetadata = $this->objectManager->getClassMetadata(get_class($object));
        $embeddedClasses = $embeddedMetadata->embeddedClasses;
        /** @var \ReflectionProperty $property */
        foreach ($embeddedMetadata->getReflectionProperties() as $property) {
            if ($property instanceof ReflectionEmbeddedProperty) {
                continue;
            }
            if (array_key_exists($property->getName(), $embeddedClasses)) {
                $this->fixNullEmbeddables($property->getValue($object), $property, $object);
            }

            if (null !== $property->getValue($object)) {
                $hasNonNullProperties = true;
            }
        }

        if (!$hasNonNullProperties) {
            $parentProperty->setValue($parentObject, null);
        }
    }
}

I'm not familiar enough with Doctrine's inner workings, and how the same might be achieved in an other way. So if you see a solution, and I might be of any help, let me know!

[beberlei]

@sneakyvv see #8022 please