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ValueError: Cannot assign "<SimpleLazyObject:
<django.contrib.auth.models.AnonymousUser object at 0x7f364795ef90>>":
"List.owner" must be a "User" instance.
ERROR: test_saving_a_POST_request (lists.tests.test_views.NewListTest)
[...]
ValueError: Cannot assign "<SimpleLazyObject:
<django.contrib.auth.models.AnonymousUser object at 0x7f364795ef90>>":
"List.owner" must be a "User" instance.
We’re moving back up to the views layer now, just doing a little tidying up. Notice that
these are in the old test for the new_list view, when we haven’t got a logged-in user. We
should only save the list owner when the user is actually logged in. The .is_authenti
cated() function we defined in comes in useful now (when they’re not
logged in, Django represents users using a class called AnonymousUser, whose .is_au
thenticated() always returns False ):
lists/views.py (ch18l023).
if form.is_valid ():
list_ = List ()
if request.user.is_authenticated():
list_ .owner = request.user
list_ .save()
form. save(for_list=list_)
[ ...]
And that gets us passing!
$ python3 manage.py test lists
Creating test database for alias 'default'...
.......................................
---------------------------------------------------------------------
Ran 39 tests in 0.237s
OK
Destroying test database for alias 'default'...
This is a good time for a commit:
$ git add lists
$ git commit -m"lists can have owners, which are saved on creation."
Final Step: Feeding Through the .name API from the Template
The last thing our outside-in design wanted came from the templates, which wanted to
be able to access a list “name” based on the text of its first item:
lists/tests/test_models.py (ch18l024).
def test_list_name_is_first_item_text (self):
list_ = List .objects.create()
Item. objects.create(list= list_, text= 'first item')
Item. objects.create(list= list_, text= 'second item')
self. assertEqual(list_.name, 'first item')
Moving Down to the Model Layer | 333