Merge pull request #1286 from Hestia-Homes/fix/predicted-baseline-rhi-fallback

Fall back to computed kWh for predicted-EPC baselines (fix 16 e2e failures)

orchestration/property_baseline_orchestrator.py

@@ -1,12 +1,11 @@
 from __future__ import annotations
 
 from collections.abc import Callable
+from typing import Optional
 
-from datatypes.epc.domain.epc_property_data import (
-    EpcPropertyData,
-    RenewableHeatIncentive,
-)
+from datatypes.epc.domain.epc_property_data import EpcPropertyData
 from domain.billing.bill import EnergyBreakdown
+from domain.sap10_calculator.calculator import SapResult
 from domain.billing.bill_derivation import BillDerivation
 from domain.property_baseline.property_baseline_performance import PropertyBaselinePerformance
 from domain.property_baseline.performance import lodged_performance
@@ -64,24 +63,40 @@ class PropertyBaselineOrchestrator:
                     if rebaselined.sap_result is not None
                     else None
                 )
-                rhi = _require_rhi(effective_epc)
+                space_heating_kwh, water_heating_kwh = _baseline_kwh(
+                    effective_epc, rebaselined.sap_result
+                )
                 baseline = PropertyBaselinePerformance(
                     lodged=lodged,
                     effective=rebaselined.effective,
                     rebaseline_reason=rebaselined.reason,
-                    space_heating_kwh=rhi.space_heating_kwh,
-                    water_heating_kwh=rhi.water_heating_kwh,
+                    space_heating_kwh=space_heating_kwh,
+                    water_heating_kwh=water_heating_kwh,
                     bill=bill,
                 )
                 uow.property_baseline.save(baseline, property_id)
             uow.commit()
 
 
-def _require_rhi(epc: EpcPropertyData) -> RenewableHeatIncentive:
+def _baseline_kwh(
+    epc: EpcPropertyData, sap_result: Optional[SapResult]
+) -> tuple[float, float]:
+    """Baseline space- and water-heating kWh for the Property.
+
+    Lodged certs carry these in the EPC's RHI block (the ADR-0007 ML target).
+    Predicted EPCs (ADR-0031) deep-copy a neighbour template that may lack an RHI
+    block, so fall back to the property's OWN computed figures from the scored
+    SapResult — a better baseline than a neighbour's lodged numbers anyway. When
+    neither source exists (no RHI and the rebaseliner scored nothing), there is
+    genuinely no demand to record, so fail noisily.
+    """
     rhi = epc.renewable_heat_incentive
-    if rhi is None:
-        raise ValueError(
-            "Effective EPC is missing renewable_heat_incentive; cannot read "
-            "baseline space-heating / hot-water kWh"
-        )
-    return rhi
+    if rhi is not None:
+        return rhi.space_heating_kwh, rhi.water_heating_kwh
+    if sap_result is not None:
+        return sap_result.space_heating_kwh_per_yr, sap_result.hot_water_kwh_per_yr
+    raise ValueError(
+        "Effective EPC has no renewable_heat_incentive and the rebaseliner "
+        "produced no SapResult; cannot establish baseline space-heating / "
+        "hot-water kWh"
+    )

tests/orchestration/test_property_baseline_orchestrator.py

@@ -165,6 +165,80 @@ class _ScoringRebaseliner(Rebaseliner):
         )
 
 
+def _property_without_rhi(*, sap_version: float = 10.2) -> Property:
+    """A predicted-style property whose EPC carries no lodged RHI block (ADR-0031
+    predicted EPCs deep-copy a template that may lack RHI)."""
+    epc = object.__new__(EpcPropertyData)
+    epc.energy_rating_current = 72
+    epc.current_energy_efficiency_band = Epc.C
+    epc.co2_emissions_current = 1.8
+    epc.energy_consumption_current = 180
+    epc.sap_version = sap_version
+    epc.renewable_heat_incentive = None
+    return Property(
+        identity=PropertyIdentity(
+            portfolio_id=1, postcode="A0 0AA", address="1 Some Street", uprn=123
+        ),
+        epc=epc,
+    )
+
+
+def _sap_result_with_heating(*, space_kwh: float, water_kwh: float) -> SapResult:
+    result = _sap_result_with_lighting()
+    object.__setattr__(result, "space_heating_kwh_per_yr", space_kwh)
+    object.__setattr__(result, "hot_water_kwh_per_yr", water_kwh)
+    # hot-water kWh must carry a fuel code for Bill Derivation (1 = mains gas).
+    object.__setattr__(result, "hot_water_fuel_code", 1)
+    return result
+
+
+def test_run_falls_back_to_computed_kwh_when_epc_has_no_rhi() -> None:
+    # Arrange — a predicted property with no lodged RHI, scored by a rebaseliner
+    # that returns a SapResult carrying the property's own computed energy.
+    property_baseline_repo = FakePropertyBaselineRepo()
+    uow = FakeUnitOfWork(
+        property=FakePropertyRepo({10: _property_without_rhi()}),
+        property_baseline=property_baseline_repo,
+    )
+    orchestrator = PropertyBaselineOrchestrator(
+        unit_of_work=lambda: uow,
+        rebaseliner=_ScoringRebaseliner(
+            _sap_result_with_heating(space_kwh=4200.0, water_kwh=1600.0)
+        ),
+        fuel_rates=FuelRatesStaticFileRepository(),
+    )
+
+    # Act
+    orchestrator.run([10])
+
+    # Assert — baseline kWh come from the computed SapResult, not a (missing) RHI.
+    (baseline, _) = property_baseline_repo.saved[0]
+    assert baseline.space_heating_kwh == 4200.0
+    assert baseline.water_heating_kwh == 1600.0
+    assert uow.commits == 1
+
+
+def test_run_raises_when_no_rhi_and_no_scored_result() -> None:
+    # Arrange — no lodged RHI AND the stub rebaseliner scores nothing: there is
+    # genuinely no source for baseline kWh, so the batch must fail noisily.
+    property_baseline_repo = FakePropertyBaselineRepo()
+    uow = FakeUnitOfWork(
+        property=FakePropertyRepo({10: _property_without_rhi()}),
+        property_baseline=property_baseline_repo,
+    )
+    orchestrator = PropertyBaselineOrchestrator(
+        unit_of_work=lambda: uow,
+        rebaseliner=StubRebaseliner(),
+        fuel_rates=FuelRatesStaticFileRepository(),
+    )
+
+    # Act / Assert
+    with pytest.raises(ValueError, match="renewable_heat_incentive"):
+        orchestrator.run([10])
+    assert property_baseline_repo.saved == []
+    assert uow.commits == 0
+
+
 def test_run_derives_and_persists_a_bill_when_the_rebaseliner_scores() -> None:
     # Arrange — a rebaseliner that hands back a SapResult with lighting energy,
     # so the orchestrator prices it into a Bill at the committed snapshot.