[Documentation] Extra lazy docs do not mention removeElement eagerness

[malarzm]

TIL that not initialized collection in EXTRA_LAZY mode will remove element with ->removeElement() from the database without waiting for a flush. I think it should be mentioned in the docs

orm/lib/Doctrine/ORM/PersistentCollection.php

Lines 355 to 365 in 0476201

	if (! $this->initialized &&
	$this->association !== null &&
	$this->association->getFetchMode() === FetchMode::EXTRA_LAZY) {
	if ($this->collection->contains($element)) {
	return $this->collection->removeElement($element);
	}
	$persister = $this->em->getUnitOfWork()->getCollectionPersister($this->association);
	return $persister->removeElement($this, $element);
	}

[DonCallisto]

As $persister here

orm/lib/Doctrine/ORM/PersistentCollection.php

Line 362 in 0476201

$persister = $this->em->getUnitOfWork()->getCollectionPersister($this->association);

could be of two types ManyToManyPersister and OneToMany persister this is the relevant code

orm/lib/Doctrine/ORM/Persisters/Collection/OneToManyPersister.php

Line 159 in e1bb9e0

public function removeElement(PersistentCollection $collection, $element)

orm/lib/Doctrine/ORM/Persisters/Collection/ManyToManyPersister.php

Line 234 in 1ab9d0b

public function removeElement(PersistentCollection $collection, $element)

I think the docs should point out this situation - where applicable - both in https://www.doctrine-project.org/projects/doctrine-orm/en/2.6/reference/working-with-associations.html#orphan-removal and https://www.doctrine-project.org/projects/doctrine-orm/en/2.6/tutorials/extra-lazy-associations.html#extra-lazy-associations

BTW the fact that ManyToManyPersister does not contemplate orphanRemoval makes me wonder if this is a bug or is done by design.

As said in #7852 that's now closed, I'm willing to work on this PR if think is worthy.

[flaushi]

If I see this correctly, one viable workaround is - and could well be mentioned in the docs - that if one needs the event listener to be called, one can replace

$entity->manyToManyCollection->removeElement($other);

with

$index = $entity->manyToManyCollection->indexOf($other);
if($index !== false)
    $entity->manyToManyCollection->remove($index);

... which will load the collection, but nevertheless I can imagine many people relying on the event listeners being called, so this is the only way to go....

[DonCallisto]

The intent of EXTRA_LAZY is to prevent the whole collection to be loaded so I don't think it has too much sense in this context.
Moreover how can one change that section of code?
Lastly, this is the intended behaviour.

[malarzm]

Closing as behaviour was changed in #7940