Method test_force_update

tests/force_insert_update/tests.py:18–62

(self)

class ForceTests(TestCase):
    def test_force_update(self):
        c = Counter.objects.create(name="one", value=1)

        # The normal case
        c.value = 2
        c.save()
        # Same thing, via an update
        c.value = 3
        c.save(force_update=True)

        # Won't work because force_update and force_insert are mutually
        # exclusive
        c.value = 4
        msg = "Cannot force both insert and updating in model saving."
        with self.assertRaisesMessage(ValueError, msg):
            c.save(force_insert=True, force_update=True)

        # Try to update something that doesn't have a primary key in the first
        # place.
        c1 = Counter(name="two", value=2)
        msg = "Cannot force an update in save() with no primary key."
        with self.assertRaisesMessage(ValueError, msg):
            with transaction.atomic():
                c1.save(force_update=True)
        c1.save(force_insert=True)

        # Won't work because we can't insert a pk of the same value.
        c.value = 5
        with self.assertRaises(IntegrityError):
            with transaction.atomic():
                c.save(force_insert=True)

        # Trying to update should still fail, even with manual primary keys, if
        # the data isn't in the database already.
        obj = WithCustomPK(name=1, value=1)
        msg = "Forced update did not affect any rows."
        # Make sure backward compatibility with DatabaseError is preserved.
        exceptions = [DatabaseError, ObjectNotUpdated, WithCustomPK.NotUpdated]
        for exception in exceptions:
            with (
                self.subTest(exception),
                self.assertRaisesMessage(DatabaseError, msg),
                transaction.atomic(),
            ):
                obj.save(force_update=True)


class InheritanceTests(TestCase):