cache.adapter.array is not available on Symfony 3.4

[vroad]

In Cache (Symfony 3.4 Docs), cache.adapter.array is listed as a valid service, but it doesn't actually work, because it's not exposed as a service.

https://github.com/symfony/framework-bundle/blob/v3.4.30/Resources/config/cache.xml
https://github.com/symfony/framework-bundle/blob/v4.3.3/Resources/config/cache.xml#L136-L143

Isn't this service introduced from Symfony 4.1? I can't find service definition in Symfony 4.0 and 3.4.

[javiereguiluz]

@vroad thanks for reporting this issue!
@nicolas-grekas do you remember if this is expected ... or if we missed adding the array adapter in 3.4? Thanks!

[nicolas-grekas]

That's been added later yes.