fix: wire boiler_efficiency_band into the reader registry (consistency guard)

test_override_component_consistency caught two real gaps: the band was in the
override_component pgEnum but (a) missing from _ROW_TYPES — so the finaliser
couldn't load its classified vocab (a latent bug the injected-vocab finaliser
tests missed), and (b) not in _COMPONENT_OVERLAYS (correct — it's an attribute
consumed by the main_heating_system overlay, not a standalone one).

Add the band to _ROW_TYPES (reader), and introduce _ATTRIBUTE_COMPONENTS to name
the classified+stored-but-no-standalone-overlay case. The guard now asserts:
pgEnum == _ROW_TYPES; and _ROW_TYPES minus attribute components == _COMPONENT_OVERLAYS.
Full repositories suite (247) + finaliser green; pyright clean.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

infrastructure/landlord_overrides/landlord_override_reader_postgres_repository.py

@@ -37,6 +37,9 @@ from infrastructure.postgres.landlord_main_fuel_override_table import (
 from infrastructure.postgres.landlord_main_heating_system_override_table import (
     LandlordMainHeatingSystemOverrideRow,
 )
+from infrastructure.postgres.landlord_boiler_efficiency_band_override_table import (
+    LandlordBoilerEfficiencyBandOverrideRow,
+)
 from infrastructure.postgres.landlord_wall_type_override_table import (
     LandlordWallTypeOverrideRow,
 )
@@ -58,6 +61,10 @@ _ROW_TYPES: dict[str, type] = {
     "construction_age_band": LandlordConstructionAgeBandOverrideRow,
     "water_heating": LandlordWaterHeatingOverrideRow,
     "main_heating_system": LandlordMainHeatingSystemOverrideRow,
+    # An attribute of the main_heating_system override (consumed by its overlay,
+    # not a standalone one) — but still classified + cached + stored, so it needs
+    # a reader entry for the finaliser to load its vocab (ADR-0068).
+    "boiler_efficiency_band": LandlordBoilerEfficiencyBandOverrideRow,
 }
 
 

repositories/property/landlord_override_overlays.py

@@ -78,6 +78,15 @@ _COMPONENT_OVERLAYS: dict[str, Callable[[str, int], Optional[EpcSimulation]]] =
 }
 
 
+# Components that are classified + stored but have **no standalone overlay** — they
+# are *attributes* consumed by another component's overlay, so they are absent from
+# `_COMPONENT_OVERLAYS` on purpose. The Boiler Efficiency Band rides the
+# main_heating_system overlay (ADR-0068), read at its call site (see
+# `_boiler_efficiency_band_for`). The override-component consistency guard treats
+# these as the reader/pgEnum-minus-overlays difference.
+_ATTRIBUTE_COMPONENTS: frozenset[str] = frozenset({"boiler_efficiency_band"})
+
+
 # Components whose overlay must be applied LAST so an explicit value wins a
 # default another overlay dragged. `apply_simulations` is last-wins and override
 # rows arrive in arbitrary order, so a `main_fuel` override must be applied after

tests/repositories/property/test_override_component_consistency.py

@@ -1,12 +1,20 @@
 """Every override component must be wired through the WHOLE chain.
 
-The finaliser reader (`_ROW_TYPES`, component -> landlord table) and the overlay
-registry (`_COMPONENT_OVERLAYS`, component -> overlay mapper) must cover exactly
-the same set of components. If a component is classified + stored but has no
-reader entry, the finaliser silently never writes its `property_overrides` rows;
-if it has no overlay entry, the row never reaches the calculator. This guard
-keeps the two registries in lock-step (it would have caught the missing
-main_fuel / glazing / construction_age_band reader entries).
+The finaliser reader (`_ROW_TYPES`, component -> landlord table), the overlay
+registry (`_COMPONENT_OVERLAYS`, component -> overlay mapper), and the
+`override_component` pgEnum mirror must stay in lock-step. If a component is
+classified + stored but has no reader entry, the finaliser silently never writes
+its `property_overrides` rows; if it has no overlay entry, the row never reaches
+the calculator; if it is missing from the pgEnum, writing/reading it throws a
+LookupError against Postgres (caught live on the Hyde portfolio-796 run). This
+guard would have caught the missing main_fuel / glazing / construction_age_band
+reader entries.
+
+The one exception is an **attribute component** (`_ATTRIBUTE_COMPONENTS`): it is
+classified + stored + read (so it *is* in `_ROW_TYPES` and the pgEnum) but is
+consumed by another component's overlay rather than having its own, so it is
+deliberately absent from `_COMPONENT_OVERLAYS` — the Boiler Efficiency Band rides
+the main_heating_system overlay (ADR-0068).
 """
 
 from __future__ import annotations
@@ -18,18 +26,27 @@ from infrastructure.landlord_overrides.landlord_override_reader_postgres_reposit
 )
 from infrastructure.postgres.property_override_table import override_component_sa_enum
 from repositories.property.landlord_override_overlays import (
+    _ATTRIBUTE_COMPONENTS,  # pyright: ignore[reportPrivateUsage]
     _COMPONENT_OVERLAYS,  # pyright: ignore[reportPrivateUsage]
 )
 
 
 def test_reader_and_overlay_registries_cover_the_same_components() -> None:
-    # Assert
-    assert set(_ROW_TYPES) == set(_COMPONENT_OVERLAYS)
+    # Every classified/stored component (`_ROW_TYPES`) has a standalone overlay,
+    # except the attribute components consumed by another overlay.
+    assert set(_ROW_TYPES) - _ATTRIBUTE_COMPONENTS == set(_COMPONENT_OVERLAYS)
+
+
+def test_attribute_components_are_read_and_stored_but_have_no_overlay() -> None:
+    # An attribute component must still be classified/read (in `_ROW_TYPES`) and
+    # stored (in the pgEnum), but must NOT appear in `_COMPONENT_OVERLAYS`.
+    assert _ATTRIBUTE_COMPONENTS <= set(_ROW_TYPES)
+    assert _ATTRIBUTE_COMPONENTS.isdisjoint(_COMPONENT_OVERLAYS)
 
 
 def test_override_component_pgenum_covers_every_component() -> None:
     # The property_overrides.override_component pgEnum mirror must list every
-    # component, or writing/reading a new-component row through it throws a
-    # LookupError against Postgres (caught live on the Hyde portfolio-796 run).
+    # classified/stored component (overlay-backed + attribute), or writing/reading
+    # a new-component row through it throws a LookupError against Postgres.
     pgenum_values = cast(list[str], getattr(override_component_sa_enum, "enums"))
-    assert set(pgenum_values) == set(_COMPONENT_OVERLAYS)
+    assert set(pgenum_values) == set(_ROW_TYPES)