I’m trying to use TestCase and setUpTestData() to create a test of a model. There are a couple of problems in the below code (marked with "TODO"s), but right now I’m just focusing on the datetime field one.
Essentially, I don’t know how to have the setUpTestData and the assertion be the same date/time since the “now” would always be just a little off between the “now” time when the test data is set up and the “now” time of the test being run. I originally tried defining a variable as a specific date/time (my “fake now”) and then assigning the variable to the date_added field, but that didn’t work because the auto_now_add field was still filled with the “real now” of when the setUpTestData was run (instead of the “fake now” of the variable).
Question
While trying to figure this out, I came across freezegun which looks like it’s addressing this problem. Before I try it out, I wanted to ask: is it normal to have to use something like freezegun (or another package) or is there a way Django users typically do this (without another package)? If people don’t usually use a package for this, how do you approach this? If people do usually use a package for this, is freezegun the standard way to go (or is there a different one that is common / best practice)?
tests.py
class CauseTests(TestCase):
@classmethod
def setUpTestData(cls):
cls.user = get_user_model().objects.create_user(
username="testuser1",
email="test@email.com",
password="testpass123",
)
cls.cause = Cause.objects.create(
#date_added is auto_now_add so it fills this field in automatically
cause_name="Cause Name",
created_by=cls.user,
)
cls.cause.users_following_cause.add(cls.user)
# MODEL TESTS #################################################################
def test_cause_model(self):
#self.assertEqual(self.cause.date_added, ) TODO: figure out how to do the testing for "now" when the "now" of the creation and the "now" of the test is different
self.assertEqual(self.cause.cause_name, "Cause Name")
self.assertEqual(self.cause.created_by.username, "testuser1")
self.assertEqual(self.cause.users_following_cause.count(), 1)
self.assertEqual(self.cause.users_following_cause.filter(username="testuser1").exists(), True)
self.assertEqual(str(self.cause), "Cause Name")
#self.assertEqual(self.cause.get_absolute_url(), "/causes/1/") # TODO: figure out how to do this when pk is UUID?
models.py
class Cause(models.Model):
id = models.UUIDField(
primary_key=True,
default=uuid.uuid4,
editable=False)
date_added = models.DateTimeField(auto_now_add=True)
created_by = models.ForeignKey(CustomUser, on_delete=models.CASCADE)
cause_name = models.CharField(max_length=100)
users_following_cause = models.ManyToManyField(CustomUser, related_name="causes_user_follows", blank=True)
