feat(fase2): promote blocking validator + IR to src

tests/test_validator.py

@@ -0,0 +1,77 @@
+"""Step 2 tests — the promoted blocking validator + IR (B1). Crafted IR, deterministic.
+
+Determinism is asserted over FIXED inputs (seed 20260624), never through an LLM. The
+out-of-range path returns a ``Rejection`` that carries no percentiles, so it can never be
+consumed as validated. Pattern: tests/spikes/test_c_validator.py.
+"""
+
+import pytest
+from pydantic import ValidationError
+
+from portfolio_optimiser.ir import SavingsProposal
+from portfolio_optimiser.reference_domain import load_reference_projects
+from portfolio_optimiser.validator import (
+    Rejection,
+    ValidatedProposal,
+    proposal_for,
+    validate_proposal,
+)
+
+_ASSUMPTIONS = {"05.2": (200.0, 230.0), "03.1": (290.0, 330.0)}
+
+
+@pytest.fixture(scope="module")
+def project():
+    return load_reference_projects()[0]  # FV42-GSV-E1
+
+
+def _valid(project) -> SavingsProposal:
+    # Affected total ~1.48M NOK; 30% feasible cap ~0.44M. Claim 200k is comfortably feasible.
+    return proposal_for(
+        project, ["05.2", "03.1"], claimed_saving_nok=200_000, assumptions=_ASSUMPTIONS
+    )
+
+
+def _out_of_range(project) -> SavingsProposal:
+    # Constructs fine (800k <= 1.48M total) but far exceeds the ~0.44M feasible cap.
+    return proposal_for(
+        project, ["05.2", "03.1"], claimed_saving_nok=800_000, assumptions=_ASSUMPTIONS
+    )
+
+
+def test_valid_proposal_yields_ordered_percentiles(project) -> None:
+    result = validate_proposal(_valid(project))
+    assert isinstance(result, ValidatedProposal)
+    assert result.p10 <= result.p50 <= result.p90  # P10 <= P50 <= P90
+    assert result.nominal_feasible > 0  # the CBC solve produced a feasible bound
+
+
+def test_out_of_range_is_structurally_blocked(project) -> None:
+    result = validate_proposal(_out_of_range(project))
+    assert isinstance(result, Rejection)
+    assert result.reason  # carries a human-readable reason
+    # A Rejection carries no percentiles -> it can never be consumed as validated.
+    with pytest.raises(AttributeError):
+        _ = result.p50  # type: ignore[attr-defined]
+
+
+def test_monte_carlo_is_reproducible(project) -> None:
+    a = validate_proposal(_valid(project))
+    b = validate_proposal(_valid(project))
+    assert isinstance(a, ValidatedProposal) and isinstance(b, ValidatedProposal)
+    assert (a.p10, a.p50, a.p90) == (b.p10, b.p50, b.p90)
+
+
+def test_pydantic_blocks_negative_quantity() -> None:
+    with pytest.raises(ValidationError):
+        SavingsProposal(
+            project_id="X",
+            measure="bad",
+            affected_items=[{"code": "A", "quantity": -1, "unit_cost": 10}],
+            claimed_saving_nok=1,
+        )
+
+
+def test_pydantic_blocks_claim_above_affected_total(project) -> None:
+    with pytest.raises(ValidationError):
+        proposal_for(project, ["05.2"], claimed_saving_nok=99_000_000)