An expired-source EPC occupies the predicted slot without stranding rows 🟥

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

tests/repositories/epc/test_epc_predicted_slot.py

@@ -80,3 +80,47 @@ def test_a_lodged_only_property_has_no_predicted_epc(db_engine: Engine) -> None:
         repo = EpcPostgresRepository(session)
         assert repo.get_predicted_for_property(9) is None
         assert repo.get_for_property(9) == epc
+
+
+def test_an_expired_source_epc_lives_in_the_predicted_slot(db_engine: Engine) -> None:
+    # Arrange — an Expired-Enhanced Prediction is persisted with source="expired"
+    # (ADR-0054): enhanced by an expired historic observation, not totally
+    # predicted — but it occupies the same predicted slot.
+    epc = _epc()
+    with Session(db_engine) as session:
+        repo = EpcPostgresRepository(session)
+        repo.save(epc, property_id=11, source="expired")
+        session.commit()
+
+    # Act / Assert — readable through the predicted slot; the lodged slot is empty.
+    with Session(db_engine) as session:
+        repo = EpcPostgresRepository(session)
+        assert repo.get_predicted_for_property(11) == epc
+        assert repo.get_predicted_for_properties([11]) == {11: epc}
+        assert repo.get_for_property(11) is None
+
+
+def test_saving_predicted_over_expired_replaces_the_slot_without_stranding(
+    db_engine: Engine,
+) -> None:
+    # Arrange — a re-ingestion can flip the slot's flavour (expired -> predicted
+    # or back); the slot holds ONE row, never a stranded stale sibling.
+    from sqlmodel import select
+
+    from infrastructure.postgres.epc_property_table import EpcPropertyModel
+
+    epc = _epc()
+    with Session(db_engine) as session:
+        repo = EpcPostgresRepository(session)
+        repo.save(epc, property_id=13, source="expired")
+        repo.save(epc, property_id=13, source="predicted")
+        session.commit()
+
+    # Act
+    with Session(db_engine) as session:
+        rows = session.exec(
+            select(EpcPropertyModel).where(EpcPropertyModel.property_id == 13)
+        ).all()
+
+    # Assert — exactly one slot row remains, the latest flavour.
+    assert [r.source for r in rows] == ["predicted"]