feat: add triple barrier labeler with first-touch logic (TASK-CODE-004)

tests/test_triple_barrier.py

@@ -0,0 +1,91 @@
+from __future__ import annotations
+
+from src.analysis.triple_barrier import TripleBarrierSpec, label_with_triple_barrier
+
+
+def test_long_take_profit_first() -> None:
+    highs = [100, 101, 103]
+    lows = [100, 99.6, 100]
+    closes = [100, 100, 102]
+    spec = TripleBarrierSpec(take_profit_pct=0.02, stop_loss_pct=0.01, max_holding_bars=3)
+    out = label_with_triple_barrier(
+        highs=highs,
+        lows=lows,
+        closes=closes,
+        entry_index=0,
+        side=1,
+        spec=spec,
+    )
+    assert out.label == 1
+    assert out.touched == "take_profit"
+    assert out.touch_bar == 2
+
+
+def test_long_stop_loss_first() -> None:
+    highs = [100, 100.5, 101]
+    lows = [100, 98.8, 99]
+    closes = [100, 99.5, 100]
+    spec = TripleBarrierSpec(take_profit_pct=0.02, stop_loss_pct=0.01, max_holding_bars=3)
+    out = label_with_triple_barrier(
+        highs=highs,
+        lows=lows,
+        closes=closes,
+        entry_index=0,
+        side=1,
+        spec=spec,
+    )
+    assert out.label == -1
+    assert out.touched == "stop_loss"
+    assert out.touch_bar == 1
+
+
+def test_time_barrier_timeout() -> None:
+    highs = [100, 100.8, 100.7]
+    lows = [100, 99.3, 99.4]
+    closes = [100, 100, 100]
+    spec = TripleBarrierSpec(take_profit_pct=0.02, stop_loss_pct=0.02, max_holding_bars=2)
+    out = label_with_triple_barrier(
+        highs=highs,
+        lows=lows,
+        closes=closes,
+        entry_index=0,
+        side=1,
+        spec=spec,
+    )
+    assert out.label == 0
+    assert out.touched == "time"
+    assert out.touch_bar == 2
+
+
+def test_tie_break_stop_first_default() -> None:
+    highs = [100, 102.1]
+    lows = [100, 98.9]
+    closes = [100, 100]
+    spec = TripleBarrierSpec(take_profit_pct=0.02, stop_loss_pct=0.01, max_holding_bars=1)
+    out = label_with_triple_barrier(
+        highs=highs,
+        lows=lows,
+        closes=closes,
+        entry_index=0,
+        side=1,
+        spec=spec,
+    )
+    assert out.label == -1
+    assert out.touched == "stop_loss"
+
+
+def test_short_side_inverts_barrier_semantics() -> None:
+    highs = [100, 100.5, 101.2]
+    lows = [100, 97.8, 98.0]
+    closes = [100, 99, 99]
+    spec = TripleBarrierSpec(take_profit_pct=0.02, stop_loss_pct=0.01, max_holding_bars=3)
+    out = label_with_triple_barrier(
+        highs=highs,
+        lows=lows,
+        closes=closes,
+        entry_index=0,
+        side=-1,
+        spec=spec,
+    )
+    assert out.label == 1
+    assert out.touched == "take_profit"