fix(portfolios): replay corporate-action cost basis (#38)

tests/test_v1_portfolios_holdings.py

@@ -8,6 +8,7 @@ from __future__ import annotations
 
 from contextlib import ExitStack
 from datetime import UTC, datetime, timezone
+from decimal import Decimal
 from unittest.mock import MagicMock, patch
 
 import pytest
@@ -286,12 +287,12 @@ class TestAC2PartialSellWacUnchanged:
         assert resp.json()["total_cost_basis"] == pytest.approx(500_000.0)
 
 
-def test_corporate_action_row_keeps_holdings_cost_basis_http_200() -> None:
+def test_corporate_action_row_returns_authoritative_holdings_cost_basis() -> None:
     buy = _make_entry(
         ledger_entry_id=1,
         side="buy",
-        quantity=20,
-        price=100,
+        quantity=1452,
+        price=1086.2341459366393,
         executed_at=datetime(2026, 9, 1, tzinfo=UTC),
     )
     corporate_action = LedgerEntry(
@@ -299,13 +300,21 @@ def test_corporate_action_row_keeps_holdings_cost_basis_http_200() -> None:
         portfolio_id=_PORTFOLIO_ID,
         source="corporate_action",
         side="stock_consolidation",
-        quantity=10,
-        price=200,
+        quantity=726,
+        price=2172.46829187,
         recorded_at=datetime(2026, 9, 2, tzinfo=UTC),
-        corporate_action={"action_type": "stock_consolidation"},
+        corporate_action={
+            "corporate_action_id": "ca-019685",
+            "action_type": "stock_consolidation",
+            "quantity_before": Decimal(1452),
+            "quantity_after": Decimal(726),
+            "average_price_after": Decimal("2172.46829187"),
+            "total_cost_basis": Decimal("1577211.97990000"),
+        },
     )
     repo = _make_service_repo(
-        portfolio=_make_portfolio(asset_quantity=10),
+        # Corporate-action replay is authoritative for the returned quantity.
+        portfolio=_make_portfolio(symbol="019685", asset_quantity=999),
         trades=[buy, corporate_action],
     )
 
@@ -316,8 +325,61 @@ def test_corporate_action_row_keeps_holdings_cost_basis_http_200() -> None:
         )
 
     assert response.status_code == 200
-    assert response.json()["cost_basis_per_unit"] == pytest.approx(100)
-    assert response.json()["total_cost_basis"] == pytest.approx(1000)
+    body = response.json()
+    assert body["current_quantity"] == pytest.approx(726)
+    assert body["cost_basis_per_unit"] == 1577211.9799 / 726
+    assert body["total_cost_basis"] == 1577211.9799
+    assert body["data_completeness_warning"] is None
+
+
+@pytest.mark.parametrize(
+    "corporate_action",
+    [
+        {"action_type": "stock_consolidation", "total_cost_basis": Decimal(1000)},
+        {
+            "action_type": "stock_consolidation",
+            "quantity_after": Decimal(0),
+            "total_cost_basis": Decimal(1000),
+        },
+        {"action_type": "stock_consolidation", "quantity_after": Decimal(10)},
+    ],
+)
+def test_corporate_action_missing_required_metadata_returns_null_costs(
+    corporate_action: dict[str, object],
+) -> None:
+    buy = _make_entry(
+        ledger_entry_id=1,
+        side="buy",
+        quantity=20,
+        price=100,
+        executed_at=datetime(2026, 9, 1, tzinfo=UTC),
+    )
+    action = LedgerEntry(
+        ledger_entry_id=2,
+        portfolio_id=_PORTFOLIO_ID,
+        source="corporate_action",
+        side="stock_consolidation",
+        quantity=10,
+        price=200,
+        recorded_at=datetime(2026, 9, 2, tzinfo=UTC),
+        corporate_action=corporate_action,
+    )
+    repo = _make_service_repo(
+        portfolio=_make_portfolio(asset_quantity=10),
+        trades=[buy, action],
+    )
+
+    with _with_repo(repo):
+        response = _make_client(_make_settings()).get(
+            _PATH,
+            headers={"Authorization": "Bearer tok"},
+        )
+
+    assert response.status_code == 200
+    body = response.json()
+    assert body["cost_basis_per_unit"] is None
+    assert body["total_cost_basis"] is None
+    assert "기업행동 metadata" in body["data_completeness_warning"]
 
 
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