#5854 workaround to avoid populating Second Level Cache from DQL queries with multiple nested DQL aliases

[Ocramius]

Provides workaround for #5854

Doesn't really fix the issue though.

The problem is following:

SELECT
    a, b, c
FROM
    A a
JOIN
    a.b b
JOIN
    b.c c

Caching a query like this one via SLC will have the DefaultQueryCache loop over associations of A, but using metadata of all DQL aliases/associations.

This workaround prevents that, but also disables caching of fetched c instances from this example.

Note: no tests provided, as existing tests already show the regression.

[Ocramius]

Hmm, not yet available. I guess nightly would be an alternative

[lcobucci]

Indeed

[lcobucci]

I think that we also have a small thing on https://github.com/doctrine/doctrine2/blob/3bc61d5f5e4aa75479dfe141e52326243972f530/tests/Doctrine/Tests/ORM/Cache/DefaultQueryCacheTest.php#L134. Shouldn't it be $state->getName() instead of $city->getName()?

[Ocramius]

Yep, that needs fixing too.

[lcobucci]

I believe we can fix those small problems in order to prevent that Notice and then think on a permanent solution.

[FabioBatSilva]

@Ocramius I made a couple changes here, hopefully will fix the issue.

[Ocramius]

Ok, seems like I'll have to do some git bisect on master: loads of issues popping up lately...

This patch is good to go meanwhile, thanks @FabioBatSilva!