(api) Simplify annotation of duration fields

Author: mfonism

tcms/rpc/api/testcase.py

@@ -1,7 +1,7 @@
 # -*- coding: utf-8 -*-
 
 from django.db.models import F, FloatField
-from django.db.models.functions import Cast
+from django.db.models.functions import Cast, Coalesce
 from django.forms import EmailField, ValidationError
 from django.forms.models import model_to_dict
 from modernrpc.core import REQUEST_KEY, rpc_method
@@ -290,8 +290,8 @@ def filter(query=None):  # pylint: disable=redefined-builtin
     # `Cast`ed to their millisecond values
     qs = (
         TestCase.objects.annotate(
-            setup_duration_sec=Cast("setup_duration", FloatField()) / 10 ** 6,
-            testing_duration_sec=Cast("testing_duration", FloatField()) / 10 ** 6,
+            setup_duration_sec=Coalesce(Cast("setup_duration", FloatField()), 0.0) / 10 ** 6,
+            testing_duration_sec=Coalesce(Cast("testing_duration", FloatField()), 0.0) / 10 ** 6,
             expected_duration_sec=F("setup_duration_sec") + F("testing_duration_sec"),
         )
         .filter(**query)

tcms/rpc/tests/test_testcase.py

@@ -185,9 +185,9 @@ def test_filter_by_product_id(self):
 
     @parameterized.expand(
         [
-            ("both_values_are_not_set", {}, None, None, None),
-            ("setup_duration_is_not_set", {"testing_duration": timedelta(minutes=5)}, None, 300, 300),
-            ("testing_duration_is_not_set", {"setup_duration": timedelta(seconds=45)}, 45, None, 45),
+            ("both_values_are_not_set", {}, 0, 0, 0),
+            ("setup_duration_is_not_set", {"testing_duration": timedelta(minutes=5)}, 0, 300, 300),
+            ("testing_duration_is_not_set", {"setup_duration": timedelta(seconds=45)}, 45, 0, 45),
             (
                 "both_values_are_set",
                 {"setup_duration": timedelta(seconds=45), "testing_duration": timedelta(minutes=5)}, 45,