Can cache empty collections

[goetas]

I should be able to cache an "empty" collection.

I have a some objects, where 90% of these have on-to-many relations with zero associated elements.
This causes doctrine to run a query each time, instead of cache it as empty relation.

(same thing should be applied to many-to-many collections)

[doctrinebot]

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[FabioBatSilva]

@goetas, Could you add some tests please ?

[goetas]

I'm looking just now inside test suite, but it is very complicated (and there are no tests that covers cache hinting... or probably i'm not able to find them). There i can look?

I think that i shoud check if storeCollectionCache is called inside AbstractEntityPersister::loadManyTo*Collection

[FabioBatSilva]

You can add unit tests in here or functional tests here and here.

Let me know if you need more info...

[goetas]

I think that te best way to test is to check if $persister->storeCollectionCache(..) is invoked.
https://github.com/doctrine/doctrine2/blob/master/lib/Doctrine/ORM/Cache/Persister/AbstractEntityPersister.php#L547
But mocking $persister that comes from uow can be complicated.

I will try to do it inside SecondLevelCacheOneToManyTest...

[goetas]

@FabioBatSilva I have added some tests

[FabioBatSilva]

@goetas Thanks, Now the build is failing for mysql and pgsql..

[goetas]

i have seen it just now. tomorrow i will try where is the problem!

[goetas]

There was a little typo mistake on previous implementation of testStoreManyToManyAssociationWhitCascade