fix(CORE-001D): close boundary review gaps

app/services/event_comparison_ui.py

@@ -117,13 +117,18 @@ class EventComparisonPageService:
     ) -> BacktestScenario:
         if not template_slugs:
             raise ValueError("Select at least one strategy template.")
+        normalized_inputs = normalize_historical_scenario_inputs(
+            underlying_units=underlying_units,
+            loan_amount=loan_amount,
+            margin_call_ltv=margin_call_ltv,
+        )
         try:
             scenario = self.comparison_service.preview_scenario_from_inputs(
                 preset_slug=preset_slug,
                 template_slugs=template_slugs,
-                underlying_units=underlying_units,
+                underlying_units=normalized_inputs.underlying_units,
-                loan_amount=loan_amount,
+                loan_amount=normalized_inputs.loan_amount,
-                margin_call_ltv=margin_call_ltv,
+                margin_call_ltv=normalized_inputs.margin_call_ltv,
             )
         except ValueError as exc:
             if str(exc) == "loan_amount must be less than initial collateral value":
@@ -134,9 +139,17 @@ class EventComparisonPageService:
                     preset.window_end,
                 )
                 if preview:
-                    _validate_initial_collateral(underlying_units, preview[0].close, loan_amount)
+                    _validate_initial_collateral(
+                        normalized_inputs.underlying_units,
+                        preview[0].close,
+                        normalized_inputs.loan_amount,
+                    )
             raise
-        _validate_initial_collateral(underlying_units, scenario.initial_portfolio.entry_spot, loan_amount)
+        _validate_initial_collateral(
+            normalized_inputs.underlying_units,
+            scenario.initial_portfolio.entry_spot,
+            normalized_inputs.loan_amount,
+        )
         return scenario
 
     def run_read_only_comparison(

app/services/price_feed.py

@@ -52,38 +52,44 @@ class PriceFeed:
         self._cache = get_cache()
 
     @staticmethod
-    def _normalize_cached_price_payload(payload: object, *, expected_symbol: str) -> PriceData:
+    def _required_payload_value(payload: Mapping[str, object], key: str, *, context: str) -> object:
+        if key not in payload:
+            raise TypeError(f"{context} is missing required field: {key}")
+        return payload[key]
+
+    @classmethod
+    def _normalize_cached_price_payload(cls, payload: object, *, expected_symbol: str) -> PriceData:
         if not isinstance(payload, Mapping):
             raise TypeError("cached price payload must be an object")
         payload_symbol = str(payload.get("symbol", expected_symbol)).strip().upper()
         normalized_symbol = expected_symbol.strip().upper()
         if payload_symbol != normalized_symbol:
             raise ValueError(f"cached symbol mismatch: {payload_symbol} != {normalized_symbol}")
-        timestamp = payload.get("timestamp")
+        timestamp = cls._required_payload_value(payload, "timestamp", context="cached price payload")
         if not isinstance(timestamp, str) or not timestamp.strip():
             raise TypeError("cached timestamp must be a non-empty ISO string")
         return PriceData(
             symbol=payload_symbol,
-            price=float(payload["price"]),
+            price=float(cls._required_payload_value(payload, "price", context="cached price payload")),
             currency=str(payload.get("currency", "USD")),
             timestamp=datetime.fromisoformat(timestamp),
             source=str(payload.get("source", "yfinance")),
         )
 
-    @staticmethod
+    @classmethod
-    def _normalize_provider_price_payload(payload: object, *, expected_symbol: str) -> PriceData:
+    def _normalize_provider_price_payload(cls, payload: object, *, expected_symbol: str) -> PriceData:
         if not isinstance(payload, Mapping):
             raise TypeError("provider price payload must be an object")
         payload_symbol = str(payload.get("symbol", expected_symbol)).strip().upper()
         normalized_symbol = expected_symbol.strip().upper()
         if payload_symbol != normalized_symbol:
             raise ValueError(f"provider symbol mismatch: {payload_symbol} != {normalized_symbol}")
-        timestamp = payload.get("timestamp")
+        timestamp = cls._required_payload_value(payload, "timestamp", context="provider price payload")
         if not isinstance(timestamp, datetime):
             raise TypeError("provider timestamp must be a datetime")
         return PriceData(
             symbol=payload_symbol,
-            price=float(payload["price"]),
+            price=float(cls._required_payload_value(payload, "price", context="provider price payload")),
             currency=str(payload.get("currency", "USD")),
             timestamp=timestamp,
             source=str(payload.get("source", "yfinance")),

tests/test_event_comparison_ui.py

@@ -11,6 +11,13 @@ from app.services.event_comparison_ui import EventComparisonFixtureHistoricalPri
 def test_event_comparison_page_service_accepts_string_and_decimal_boundary_values() -> None:
     service = EventComparisonPageService()
 
+    preview = service.preview_scenario(
+        preset_slug="gld-jan-2024-selloff",
+        template_slugs=("protective-put-atm-12m",),
+        underlying_units="1000.0",
+        loan_amount=Decimal("68000.0"),
+        margin_call_ltv="0.75",
+    )
     report = service.run_read_only_comparison(
         preset_slug="gld-jan-2024-selloff",
         template_slugs=("protective-put-atm-12m", "protective-put-95pct-12m"),
@@ -19,6 +26,9 @@ def test_event_comparison_page_service_accepts_string_and_decimal_boundary_value
         margin_call_ltv="0.75",
     )
 
+    assert preview.initial_portfolio.underlying_units == 1000.0
+    assert preview.initial_portfolio.loan_amount == 68000.0
+    assert preview.initial_portfolio.margin_call_ltv == 0.75
     assert report.scenario.initial_portfolio.underlying_units == 1000.0
     assert report.scenario.initial_portfolio.loan_amount == 68000.0
     assert report.scenario.initial_portfolio.margin_call_ltv == 0.75

tests/test_price_feed.py

@@ -75,6 +75,35 @@ async def test_price_feed_discards_malformed_cached_payload_and_refetches(monkey
     assert feed._cache.writes[0][0] == "price:GLD"
 
 
+@pytest.mark.asyncio
+async def test_price_feed_discards_cached_payload_missing_required_price_and_refetches(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    feed = PriceFeed()
+    feed._cache = _CacheStub({"price:GLD": {"symbol": "GLD", "timestamp": "2026-03-26T12:00:00+00:00"}})
+
+    async def fake_fetch(symbol: str):
+        return {
+            "symbol": symbol,
+            "price": 205.0,
+            "currency": "USD",
+            "timestamp": datetime(2026, 3, 26, 12, 3, tzinfo=timezone.utc),
+            "source": "yfinance",
+        }
+
+    monkeypatch.setattr(feed, "_fetch_yfinance", fake_fetch)
+
+    data = await feed.get_price("GLD")
+
+    assert data == PriceData(
+        symbol="GLD",
+        price=205.0,
+        currency="USD",
+        timestamp=datetime(2026, 3, 26, 12, 3, tzinfo=timezone.utc),
+        source="yfinance",
+    )
+
+
 @pytest.mark.asyncio
 async def test_price_feed_rejects_invalid_provider_payload() -> None:
     feed = PriceFeed()