From 04484edc6785dcdfa93736d56f4b5dd63107dec5 Mon Sep 17 00:00:00 2001
From: Khalim Conn-Kowlessar <kconnkowlessar@gmail.com>
Date: Wed, 1 Jul 2026 14:33:24 +0000
Subject: [PATCH] =?UTF-8?q?Re-map=20old-storage=20HHRSH=20overrides=20onto?=
 =?UTF-8?q?=20the=20high-heat-retention=20archetype=20=F0=9F=9F=A5?=
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Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
---
 scripts/reclassify_hhrsh_storage.py           | 12 ++++
 .../scripts/test_reclassify_hhrsh_storage.py  | 70 +++++++++++++++++++
 2 files changed, 82 insertions(+)
 create mode 100644 scripts/reclassify_hhrsh_storage.py
 create mode 100644 tests/scripts/test_reclassify_hhrsh_storage.py

diff --git a/scripts/reclassify_hhrsh_storage.py b/scripts/reclassify_hhrsh_storage.py
new file mode 100644
index 000000000..da4fbce82
--- /dev/null
+++ b/scripts/reclassify_hhrsh_storage.py
@@ -0,0 +1,12 @@
+"""One-time re-classification of HHRSH overrides funnelled into old storage.
+
+Placeholder — decision function stubbed; filled in GREEN.
+"""
+
+from __future__ import annotations
+
+from collections.abc import Iterable
+
+
+def hhrsh_storage_corrections(stored: Iterable[tuple[str, str]]) -> dict[str, str]:
+    raise NotImplementedError
diff --git a/tests/scripts/test_reclassify_hhrsh_storage.py b/tests/scripts/test_reclassify_hhrsh_storage.py
new file mode 100644
index 000000000..c3b025c53
--- /dev/null
+++ b/tests/scripts/test_reclassify_hhrsh_storage.py
@@ -0,0 +1,70 @@
+"""The HHRSH reclassify maps the "old storage" dumping ground onto the high-heat-
+retention archetype, leaves other storage subtypes alone, and is idempotent
+(#1376 / ADR-0044)."""
+
+from __future__ import annotations
+
+from domain.epc.property_overlays.main_heating_system_overlay import (
+    main_heating_overlay_for,
+)
+from domain.epc.property_overrides.main_heating_guard import main_heating_guard
+from domain.epc.property_overrides.main_heating_system_type import (
+    MainHeatingSystemType,
+)
+from scripts.reclassify_hhrsh_storage import hhrsh_storage_corrections
+
+
+def test_hhrsh_rows_are_remapped_off_old_storage() -> None:
+    # Arrange — HHRSH funnelled into old storage (the bug), plus a genuinely-old
+    # storage row and a gas row that must be left untouched.
+    stored = [
+        (
+            "electric storage systems: high heat retention storage heaters",
+            "Electric storage heaters, old",
+        ),
+        (
+            "electric storage systems: old (large volume) storage heaters",
+            "Electric storage heaters, old",
+        ),
+        ("gas boiler", "Gas boiler, regular"),
+    ]
+
+    # Act
+    corrections = hhrsh_storage_corrections(stored)
+
+    # Assert — only the HHRSH row moves, to its own archetype.
+    assert corrections == {
+        "electric storage systems: high heat retention storage heaters": (
+            "Electric storage heaters, high heat retention"
+        )
+    }
+
+
+def test_every_guard_target_round_trips_to_a_resolvable_archetype() -> None:
+    # The HHRSH archetype the guard emits must decode to a real SAP heating code —
+    # a guard/overlay drift can't silently write an unmodellable value (ADR-0044).
+    member = main_heating_guard(
+        "Electric Storage Systems: High heat retention storage heaters"
+    )
+
+    assert member is not None
+    assert member in MainHeatingSystemType
+    simulation = main_heating_overlay_for(member.value, 0)
+    assert simulation is not None
+    assert simulation.heating is not None
+    assert simulation.heating.sap_main_heating_code is not None
+
+
+def test_already_corrected_rows_need_no_change() -> None:
+    # Act / Assert — idempotent.
+    assert (
+        hhrsh_storage_corrections(
+            [
+                (
+                    "electric storage systems: high heat retention storage heaters",
+                    "Electric storage heaters, high heat retention",
+                )
+            ]
+        )
+        == {}
+    )