Add a cookbook entry to explain how to clear the cache before tests

[adrienbrault]

Hi,

Following @fabpot's suggestion on symfony/symfony-standard#421

[wouterj]

you should remove this line, there shouldn't be an empty line between the file comment and the code

[adrienbrault]

@wouterj Thanks for the review, updated

[bamarni]

IMO a dedicated cookbook entry isn't appropriate for this, it would make more sense as a small note in the testing section, because this tutorial isn't so much related to symfony.

Out of curiosity, what issue can occur if one doesn't clear its cache between tests? As in the SE the test environment extends the dev environment, wich usually auto-regenerates some cache files when it's needed.

Edit: nevermind, it's explained in the first section of your change ;)

[weaverryan]

Hi Adrien!

I've merged this in with a few tweaks, including making the entry sound a little bit more generic (i.e. about customizing the bootstrap process of a test).

@bamarni I agreed with you initially about not having this in its own cookbook entry, but I think it's ok because (a) it's not a critical, core feature to testing and (b) it's much more "findable" (via google) as a standalone article. I think this type of separation can be a good thing - keeping the core articles smaller with more interlinking.

Thanks everyone!