test: define lagged factor-to-execution contract

tests/test_research_pipeline.py

@@ -0,0 +1,150 @@
+"""No-lookahead factor-score to execution-audit integration contracts."""
+
+from __future__ import annotations
+
+import pandas as pd
+import pytest
+
+from quant_engine.execution import ExecutionConfig
+from quant_engine.research_pipeline import (
+    FactorExecutionResult,
+    TargetWeightSchedule,
+    run_factor_execution_research,
+    schedule_target_weights,
+)
+
+
+def _calendar() -> pd.DatetimeIndex:
+    return pd.date_range("2026-01-05", periods=4, freq="B")
+
+
+def _factor_scores() -> pd.DataFrame:
+    dates = _calendar()
+    return pd.DataFrame(
+        {"A": [2.0, 0.0], "B": [1.0, 3.0]},
+        index=dates[:2],
+    )
+
+
+def _next_session_open_prices() -> pd.DataFrame:
+    dates = _calendar()
+    return pd.DataFrame(
+        {"A": [1.0, 10.0, 10.0, 10.0], "B": [1.0, 10.0, 20.0, 20.0]},
+        index=dates,
+    )
+
+
+def test_schedule_target_weights_maps_signal_to_next_trading_session() -> None:
+    dates = _calendar()
+    decision_weights = pd.DataFrame(
+        {"A": [1.0, 0.0], "B": [0.0, 1.0]},
+        index=dates[:2],
+    )
+
+    schedule = schedule_target_weights(decision_weights, dates, lag_sessions=1)
+
+    assert isinstance(schedule, TargetWeightSchedule)
+    assert schedule.lag_sessions == 1
+    pd.testing.assert_series_equal(
+        schedule.signal_to_execution,
+        pd.Series(dates[1:3], index=dates[:2], name="execution_date"),
+    )
+    expected = decision_weights.copy()
+    expected.index = dates[1:3]
+    expected.index.name = "execution_date"
+    pd.testing.assert_frame_equal(schedule.execution_weights, expected)
+    assert (schedule.execution_weights.index > schedule.signal_to_execution.index).all()
+
+
+def test_factor_execution_research_uses_next_session_prices() -> None:
+    config = ExecutionConfig(
+        commission_bps=0,
+        stamp_tax_bps=0,
+        slippage_bps=0,
+        min_trade_amount=0,
+    )
+
+    result = run_factor_execution_research(
+        _factor_scores(),
+        _next_session_open_prices(),
+        top_k=1,
+        execution_price_field="open",
+        initial_cash=1_000.0,
+        config=config,
+    )
+
+    assert isinstance(result, FactorExecutionResult)
+    assert result.execution_price_field == "open"
+    assert result.execution.daily_executions[0].date == str(_calendar()[1])
+    assert result.execution.positions[0].holdings == {"A": 100.0}
+    assert result.execution.positions[1].holdings == {"B": 50.0}
+    assert result.execution.final_portfolio_value == pytest.approx(1_000.0)
+
+
+def test_factor_execution_result_snapshots_research_inputs() -> None:
+    scores = _factor_scores()
+    prices = _next_session_open_prices()
+
+    result = run_factor_execution_research(
+        scores,
+        prices,
+        top_k=1,
+        execution_price_field="open",
+    )
+    scores.iloc[0, 0] = -999.0
+    prices.iloc[1, 0] = 999.0
+
+    assert result.factor_scores.iloc[0, 0] == 2.0
+    assert result.execution.positions[0].holdings["A"] < 200_000.0
+
+
+@pytest.mark.parametrize("lag_sessions", [0, -1, True])
+def test_schedule_target_weights_requires_positive_integer_lag(lag_sessions: int) -> None:
+    with pytest.raises(ValueError, match="lag_sessions"):
+        schedule_target_weights(
+            pd.DataFrame({"A": [1.0]}, index=_calendar()[:1]),
+            _calendar(),
+            lag_sessions=lag_sessions,
+        )
+
+
+def test_schedule_target_weights_rejects_signal_outside_trading_calendar() -> None:
+    weekend = pd.Timestamp("2026-01-10")
+    with pytest.raises(ValueError, match="signal dates must be trading sessions"):
+        schedule_target_weights(
+            pd.DataFrame({"A": [1.0]}, index=[weekend]),
+            _calendar(),
+        )
+
+
+def test_schedule_target_weights_rejects_missing_future_execution_session() -> None:
+    dates = _calendar()
+    with pytest.raises(ValueError, match="future execution session"):
+        schedule_target_weights(
+            pd.DataFrame({"A": [1.0]}, index=dates[-1:]),
+            dates,
+        )
+
+
+def test_factor_execution_research_requires_explicit_price_field() -> None:
+    with pytest.raises(ValueError, match="execution_price_field"):
+        run_factor_execution_research(
+            _factor_scores(),
+            _next_session_open_prices(),
+            top_k=1,
+            execution_price_field="",
+        )
+
+
+def test_factor_execution_research_accepts_empty_scores() -> None:
+    scores = pd.DataFrame(columns=["A", "B"], index=pd.DatetimeIndex([]), dtype=float)
+
+    result = run_factor_execution_research(
+        scores,
+        _next_session_open_prices(),
+        top_k=1,
+        execution_price_field="open",
+    )
+
+    assert result.schedule.execution_weights.empty
+    assert result.execution.positions == ()