fix: Updates DummySchedule to fix broken tests

Tests were failing due to receiving created and start_date in both
positional and keyword args via the init method. I've opted to just
remove the custom init method and just specify the created date
when making a DummySchedule

tests/test_api.py

@@ -41,7 +41,9 @@ def setUp(self):
         self.enrollment = DummyEnrollment(user=self.user, course=self.course)
         self.enrollment.save()
 
-        self.schedule = DummySchedule(enrollment=self.enrollment, start_date=datetime(2019, 4, 1))
+        self.schedule = DummySchedule(
+            enrollment=self.enrollment, created=datetime(2019, 4, 1), start_date=datetime(2019, 4, 1)
+        )
         self.schedule.save()
 
         dummy_schedule_patcher = patch('edx_when.utils.Schedule', DummySchedule)
@@ -177,7 +179,7 @@ def test_get_dates_for_course(self):
         enrollment2 = DummyEnrollment(user=self.user, course=course2)
         enrollment2.save()
 
-        schedule2 = DummySchedule(enrollment=enrollment2, start_date=datetime(2019, 4, 1))
+        schedule2 = DummySchedule(enrollment=enrollment2, created=datetime(2019, 4, 1), start_date=datetime(2019, 4, 1))
         schedule2.save()
 
         api.set_dates_for_course(new_items[0][0].course_key, new_items)

tests/test_models.py

@@ -25,9 +25,15 @@ class TestDatePolicy(TestCase):
     @ddt.data(
         (None, None, None, None),
         (datetime(2020, 1, 1), None, None, datetime(2020, 1, 1)),
-        (datetime(2020, 1, 1), None, DummySchedule(start_date=datetime(2020, 3, 1)), datetime(2020, 1, 1)),
-        (None, timedelta(days=1), DummySchedule(start_date=datetime(2020, 1, 1)), datetime(2020, 1, 2)),
-        (datetime(2020, 3, 1), timedelta(days=1), DummySchedule(start_date=datetime(2020, 1, 1)), datetime(2020, 1, 2)),
+        (datetime(2020, 1, 1), None,
+            DummySchedule(created=datetime(2020, 3, 1), start_date=datetime(2020, 3, 1)), datetime(2020, 1, 1)
+        ),
+        (None, timedelta(days=1),
+            DummySchedule(created=datetime(2020, 1, 1), start_date=datetime(2020, 1, 1)), datetime(2020, 1, 2)
+        ),
+        (datetime(2020, 3, 1), timedelta(days=1),
+            DummySchedule(created=datetime(2020, 1, 1), start_date=datetime(2020, 1, 1)), datetime(2020, 1, 2)
+        ),
     )
     @ddt.unpack
     def test_actual_date(self, abs_date, rel_date, schedule, expected):
@@ -47,14 +53,14 @@ def test_actual_date_failure(self, abs_date, rel_date, schedule):
     def test_actual_date_schedule_after_end(self):
         # This only applies for relative dates so we are not testing abs date.
         policy = DatePolicy(rel_date=timedelta(days=1))
-        schedule = DummySchedule(start_date=datetime(2020, 4, 1))
+        schedule = DummySchedule(created=datetime(2020, 4, 1), start_date=datetime(2020, 4, 1))
         self.assertIsNone(policy.actual_date(schedule, end_datetime=datetime(2020, 1, 1)))
 
     def test_actual_date_schedule_after_cutoff(self):
         # This only applies for relative dates so we are not testing abs date.
         day = timedelta(days=1)
         policy = DatePolicy(rel_date=day)
-        schedule = DummySchedule(start_date=datetime(2020, 4, 1))
+        schedule = DummySchedule(created=datetime(2020, 4, 1), start_date=datetime(2020, 4, 1))
         self.assertIsNone(policy.actual_date(schedule, cutoff_datetime=(schedule.created - day)))
         self.assertIsNotNone(policy.actual_date(schedule, cutoff_datetime=(schedule.created + day)))
 

tests/test_models_app/models.py

@@ -42,9 +42,3 @@ class DummySchedule(models.Model):
         db_index=True,
         help_text='Date this schedule went into effect'
     )
-
-    def __init__(self, *args, created=None, start_date=None, **kwargs):
-        # Ensure we have a created value, if possible
-        if not created and start_date:
-            created = start_date
-        super().__init__(*args, created=created, start_date=start_date, **kwargs)