Hey!

I see that this is your first PR. That is great! Welcome!

Symfony has a contribution guide which I suggest you to read.

In short:

• Always add tests
• Keep backward compatibility (see https://symfony.com/bc).
• Bug fixes must be submitted against the lowest maintained branch where they apply (see https://symfony.com/releases)
• Features and deprecations must be submitted against the 5.x branch.

Review the GitHub status checks of your pull request and try to solve the reported issues. If some tests are failing, try to see if they are failing because of this change.

When two Symfony core team members approve this change, it will be merged and you will become an official Symfony contributor!
If this PR is merged in a lower version branch, it will be merged up to all maintained branches within a few days.

I am going to sit back now and wait for the reviews.

Cheers!

Carsonbot

Could you add a testcase?

@OskarStark Sure -- just noticed I had missed that part, but got distracted with new years stuff! ... will try and get one up shortly.

Thank you 😊

Now rebased for 4.4

@victormacko Can you have a look at the tests as they seem to be broken by your changes.

Done @fabpot .. let me know if there's anything I can do to help with the other failing tests - one is a class-ref issue, and another due to commits (both of which i'm not sure about how to assist with)

@victormacko Something went wrong here as there are many unrelated changes. Can you rebase on the current 4.4 branch?

Thank you @victormacko.

Nps, thanks @xabbuh -- not sure what happened either, but appreciate your help :)

unfortunately this issue still persists in 5.4.10 if indexBy is using a subproperty of a relation n:1 property of the relation. Symfony/Doctrine itself is working fine doing this and correctly indexing the relations, but the mentioned exception is thrown when resolving validations.

Example:

class Article {
    /**
     * @var ArticleAttribute[]
     * @ORM\OneToMany(targetEntity=ArticleAttribute::class, mappedBy="article", cascade={"all"}, indexBy="attribute.name")
     */
    private $attributes;
}

class ArticleAttribute {
    /**
     * @var Attribute
     * @ORM\ManyToOne(targetEntity=Attribute::class)
     * @ORM\JoinColumn(nullable=false)
     */
    private $attribute;
}

class Attribute {
    /**
     * @var string
     * @ORM\Column(type="string", length=30, unique=true)
     */
    private $name;
}

any ideas?

@da-anda please open a new ticket instead of commenting on a PR merged more than 1 year ago. Otherwise, the only way to find back the discussion is through notifications (as nobody goes checking old merged PRs for new comments), and not everyone gets notifications for all new comments.
and please provide full details to help debugging.

done