Add tests for Guest model and corresponding fixtures

Introduce unit tests for the Guest model covering properties, methods, and behaviors such as creation, status updates, and permissions. Add `guest_fixture` in `conftest.py` to streamline reusable test setup for Guest instances.

backend/tests/models/test_guest.py

@@ -0,0 +1,102 @@
+# tests/models/test_guest.py
+import uuid
+from datetime import datetime, timezone
+from app.models.guest import Guest, GuestStatus
+
+
+def test_create_guest(db_session, mock_user):
+    # Arrange
+    guest = Guest(
+        id=uuid.uuid4(),
+        event_id=uuid.uuid4(),
+        invited_by=mock_user.id,
+        full_name="Jane Smith",
+        email="janesmith@example.com",
+        phone="9876543210",
+        invitation_code="INV654321",
+        status=GuestStatus.PENDING,
+        max_additional_guests=3,
+        dietary_restrictions="Vegetarian",
+        notes="VIP Guest",
+        custom_fields={"special_request": "Near the buffet"},
+    )
+    db_session.add(guest)
+
+    # Act
+    db_session.commit()
+    created_guest = db_session.query(Guest).filter_by(id=guest.id).first()
+
+    # Assert
+    assert created_guest is not None
+    assert created_guest.full_name == "Jane Smith"
+    assert created_guest.email == "janesmith@example.com"
+    assert created_guest.phone == "9876543210"
+    assert created_guest.invitation_code == "INV654321"
+    assert created_guest.status == GuestStatus.PENDING
+    assert created_guest.max_additional_guests == 3
+    assert created_guest.dietary_restrictions == "Vegetarian"
+    assert created_guest.notes == "VIP Guest"
+    assert created_guest.custom_fields == {"special_request": "Near the buffet"}
+
+
+def test_total_guests_property(guest_fixture):
+    # Act
+    total_guests = guest_fixture.total_guests
+
+    # Assert
+    assert total_guests == 2  # 1 guest + 1 additional guest
+
+
+def test_has_responded_property(guest_fixture):
+    # Act
+    responded = guest_fixture.has_responded
+
+    # Assert
+    assert responded is False  # Default status is INVITED
+
+    # Update status to CONFIRMED
+    guest_fixture.status = GuestStatus.CONFIRMED
+    assert guest_fixture.has_responded is True
+
+
+def test_update_status_method(guest_fixture):
+    # Act: Update status to CONFIRMED
+    guest_fixture.update_status(GuestStatus.CONFIRMED)
+
+    # Assert: Status is updated and response date is set
+    assert guest_fixture.status == GuestStatus.CONFIRMED
+    assert guest_fixture.response_date is not None
+    assert abs(
+        (guest_fixture.response_date - datetime.now(timezone.utc)).total_seconds()) < 10  # Response date is recent
+
+
+def test_repr_method(guest_fixture):
+    # Act
+    repr_output = repr(guest_fixture)
+
+    # Assert
+    assert repr_output == f"<Guest {guest_fixture.full_name} ({guest_fixture.status.value})>"
+
+
+def test_invitation_sent_at(guest_fixture):
+    # Assert
+    assert guest_fixture.invitation_sent_at is not None
+    assert abs((guest_fixture.invitation_sent_at - datetime.now(timezone.utc)).total_seconds()) < 10
+
+
+def test_guest_is_blocked(guest_fixture):
+    # Act & Assert
+    assert guest_fixture.is_blocked is False
+
+    # Set guest to blocked
+    guest_fixture.is_blocked = True
+    assert guest_fixture.is_blocked is True
+
+
+def test_can_bring_guests(guest_fixture):
+    # Act & Assert
+    assert guest_fixture.can_bring_guests is True
+
+    # Remove guest's "bring guests" permission
+    guest_fixture.can_bring_guests = False
+    assert guest_fixture.can_bring_guests is False