Testing

iommi ships with a small set of helpers in iommi.test_helpers to make it easy to test your own frontend. The most important of these is do_post, which simulates a user filling out a form and submitting it.

do_post

Testing a form by hand is tedious: a real POST has to include the CSRF token, the hidden post target, and the current value of every field, not just the one value you care about. do_post takes care of all of that for you.

It renders the form, extracts the default post data, merges the keyword arguments you pass on top, and binds the form to a matching POST request:

class AlbumForm(Form):
    name = Field()
    year = Field.integer()

form = do_post(AlbumForm.create(), name='Bringing It All Back Home', year='1965')

The returned form is already bound to the POST request, so you can assert on validation and on the parsed values:

assert form.is_valid()
assert form.fields.name.value == 'Bringing It All Back Home'
assert form.fields.year.value == 1965

Note that you need a form with a post target, so remember to use .create(), .edit() or .delete().

Key validation

By default do_post checks that every key you pass actually exists in the rendered form. This catches typos in your tests so you don’t silently assert against a value that was never posted. If you need to post a key that isn’t a plain field (for example a virtual key for inserting a new row in an EditTable, like columns__name__field/-1), turn the check off with do_post_key_validation=False:

form = do_post(AlbumForm.create(), do_post_key_validation=False, name='Highway 61 Revisited', year='1965')

Building requests

iommi.test_helpers also provides helpers for building request objects:

• req(method, **data) builds a request from an anonymous user.

• user_req(method, **data) builds a request from a normal authenticated user.

• staff_req(method, **data) builds a request from an authenticated staff/superuser.

do_post uses req by default. Pass request_builder to submit the form as a different user, which is handy for testing access control:

class AlbumForm(Form):
    name = Field()

form = do_post(AlbumForm.create(), name='Slipping Into Darkness', request_builder=staff_req)

These helpers can also be used on their own to build a request to bind any iommi component to:

page = AlbumForm.create().bind(request=user_req('get'))