Misleading ORMInvalidArgumentException message

[foaly-nr1]

Given two entities and a random class with similar name (to confuse the developer, but could be anything really):

/** @Entity */
class User
{
    // ...

    /**
     * @ManyToMany(targetEntity="Group", inversedBy="users", cascade={"all"})
     */
    private $groups;

    public function __construct() {
        $this->groups = new \Doctrine\Common\Collections\ArrayCollection();
    }
}

/** @Entity */
class Group
{
    /**
     * @ManyToMany(targetEntity="User", mappedBy="groups")
     */
    private $users;

    public function __construct() {
        $this->users = new \Doctrine\Common\Collections\ArrayCollection();
    }
}

class Group2
{}

If you add an instance of Group2 to User#$groups and try to persist, an exception will be thrown from Doctrine\ORM\UnitOfWork:832:

if (! ($entry instanceof $targetClass->name)) {
  throw ORMInvalidArgumentException::invalidAssociation($targetClass, $assoc, $entry);
}

However, instead of reading like:

Expected value of type "AppBundle\Entity\Group" for association field "AppBundle\Entity\User#$groups", got "AppBundle\Entity\Group2" instead.

It reads like:

Expected value of type "Doctrine\Common\Collections\Collection|array" for association field "AppBundle\Entity\User#$groups", got "AppBundle\Entity\Group2" instead.

Simply because the $expectedType isn't set correctly for many-to-many associations in Doctrine\ORM:201:

$expectedType = 'Doctrine\Common\Collections\Collection|array';

if (($assoc['type'] & ClassMetadata::TO_ONE) > 0) {
    $expectedType = $targetClass->getName();
}

[asiermarques]

+1 this is a severe UX problem. That error message must be changed in order to avoid misunderstandings.

[lcobucci]

@foaly-nr1 could you please send us a failing test case that reproduces that behaviour? It would help us a lot to identify and fix the issue you're describing.

You can find examples on https://github.com/doctrine/doctrine2/tree/388afb46d0cb3ed0c51332e8df0de9e942c2690b/tests/Doctrine/Tests/ORM/Functional/Ticket