Updating from symfony/doctrine-bridge 4.4.15 to 4.4.16 results in doctrine mapping exception

[tannyl]

Sylius version affected: 1.8.2 (most likely others as well)

Description
When updating from symfony/doctrine-bridge 4.4.15 to 4.4.16 this breaks Sylius.
When running bin/console cache:clear after updating to 4.4.16 this results in the followering error:

In MappingException.php line 621:
  Cannot find a field on 'Sylius\Component\Core\Model\ChannelPricing' that is mapped to column 'channelCode'. Either the field does not exi  
  st or an association exists but it has multiple join columns.

I suspect that this is due to the changes to symfony/doctrine-bridge/PropertyInfo/DoctrineExtractor.php as seen her: symfony/doctrine-bridge@v4.4.15...v4.4.16

Steps to reproduce
Update symfony/doctrine-bridge from 4.4.15 to 4.4.16 and run bin/console cache:clear

[tannyl]

To try and temporally fix the problem I added this to our extended ProductVariant

    /**
     * @ORM\OneToMany(targetEntity="Sylius\Component\Core\Model\ChannelPricingInterface", mappedBy="productVariant", orphanRemoval=true, indexBy="channel_code", cascade={"ALL"})
     *
     * @var Collection
     */
    protected $channelPricings;

The indexBy is not changed from "channelCode" to "channel_code", which fixes the above error.

By a new problem arises. The collection that is returned does not use the "channel_code" as key, as it should.

In 4.4.15 it would return this as expected (without the above change to IndexBy ofcourse:

But now in 4.4.16 it ignores the indexBy and uses numbers as keys. Which in turn breaks Sylius again, as it never finds any price for any of the variants.

Strangely enough if I use "id" in indexBy it works as expected, and they entries in the collection is using the ids as keys.

So I guess symfony/doctrine-bridge 4.4.16 is broken.

[lchrusciel]

The problem still has to be fixed on Symfony/DoctrineBridge

[lucaball]

Yes, but it is reported, see symfony/symfony#38861