Add test

aleksis/core/tests/regression/test_regression.py

 import base64
+from datetime import date
 
 from django.contrib.auth import get_user_model
 from django.test import override_settings
@@ -6,7 +7,7 @@ from django.urls import reverse
 
 import pytest
 
-from aleksis.core.models import Group, OAuthApplication, Person
+from aleksis.core.models import Holiday, Group, OAuthApplication, Person
 
 pytestmark = pytest.mark.django_db
 
@@ -147,3 +148,16 @@ def test_change_password_not_logged_in(client):
 
     assert response.status_code == 200
     assert "Please login to see this page." in response.content.decode("utf-8")
+
+
+def test_all_day_events_end_date():
+    """Tests that CalendarEvent's value method returns a non-inclusive end date for all day events.
+
+    https://edugit.org/AlekSIS/official/AlekSIS-Core/-/issues/1199
+    """
+    holiday = Holiday.objects.create(
+        date_start=date(2024, 2, 1), date_end=date(2024, 2, 1), holiday_name="Test Holiday"
+    )
+
+    assert holiday.value_start_datetime(holiday) == date(2024, 2, 1)
+    assert holiday.value_end_datetime(holiday) == date(2024, 2, 2)