Test fixture support

[Caleb Davis]

A few tickets are blocking on being able to rip test data into the
database, and some giant put me on his shoulders and then I saw the
promised land of test fixtures. We need to support test fixtures.

[Christopher Allan Webber]

There are two possible ways we could do this, too.


-  We could make use of the envball stuff we have. That would be
   easiest, maybe?
-  We could write something different. The envball stuff exports to
   I think binary database files which aren't so great for fixtures.
   What I'd really like are bson->json exports of the data and not
   gzipped tarballs... that would make it easier for us to edit our
   fixture data going forward as things change in a git-friendly way.

`#1 </issues/1>`_ is probably faster, #2 is probably nicer.

[Caleb Davis]

2 would be fine I think. A thin wrapper around mongo{import/export} would seem to do the trick!
===============================================================================================

`http://www.mongodb.org/display/DOCS/Import+Export+Tools#ImportExportTools-mongoimport <http://www.mongodb.org/display/DOCS/Import+Export+Tools#ImportExportTools-mongoimport>`_

[Elrond]

A simple start: Creating the test user in the database. I factored
that out into a tool function.
My branch: ``misc/fixture_add_user``.
If nobody cries "stupid idea" or "found a bug", I'll merge/push on
sunday.

Okay, merged. (commit ea5a5b15a3d5)

[Christopher Allan Webber]

The requirements for this have massively changed now that we're
moving to SQL, but I say "leave it open for now".

[Will Kahn-Greene]

The original url for this bug was ​http://bugs.foocorp.net/issues/570 .
Relations:
#142: related, #55: related, #379: blocked

[Elrond]

This will be interesting after sql lands.
sql hopefully lands in the next release.
So this will be after the next release, probably.

Of course, if someone wants to take it, go for it!

[Christopher Allan Webber]

I'm going to kill this one.

I saw a talk at pycon that significantly convinced me that test fixtures are the wrong way to go. See:

​http://www.youtube.com/watch?v=ickNQcNXiS4&feature=player_embedded

starting at 16:26

All sorts of reasons given for why this is bad!

Instead he suggests writing code like this:

def create_profile(**kwargs):
    defaults = {
        "likes_cheese": True,
        "age": 32,
        "address": "3815 Brookside Dr",
    }
    defaults.update(kwargs)
    if "user" not in defaults:
        defaults["user"] = create_user()
    return Profile.objects.create(
        **defaults)

and using that to *only* change the fields that you need to test for each thing you're trying out.

fixture_add_user() as elrond made above already pretty close to this.

Anyway, wontfix'ing my own bug! :)

[Will Kahn-Greene]

I didn't even know this bug was around.

Erik Rose's talk at PyCon 2012 also talk about problems with testing using fixtures:

​http://pyvideo.org/video/634/speedily-practical-large-scale-tests