feat(s54): value_report roll-up builder over SavingsLedger accessors

tests/test_value_report.py

@@ -0,0 +1,84 @@
+"""S5.4 — verdirapport unit tests: roll-up correctness (SC1), exact NOK (SC2), determinism (SC6).
+
+In-process build over a hand-constructed ``SavingsLedger``; local ``_entry(...)`` factory (copied
+from ``tests/test_ledger.py:22-37``). The roll-up must call the ledger accessors
+(``per_project_total`` / ``portfolio_total`` / ``overlaps``), never re-sum ``.entries`` (double-count
+risk on cross-dimension overlaps).
+"""
+
+from __future__ import annotations
+
+from portfolio_optimiser.ledger import LedgerEntry, SavingsLedger, stamp
+from portfolio_optimiser.value_report import (
+    ProvenanceLine,
+    build_value_report,
+)
+
+_TS = "2026-07-06T00:00:00Z"
+
+
+def _entry(
+    project_id: str,
+    candidate_identity: str,
+    amount_ore: int,
+    *,
+    dimension: str = "energi",
+    verdict_id: str = "v1",
+) -> LedgerEntry:
+    return LedgerEntry(
+        project_id=project_id,
+        dimension=dimension,
+        candidate_identity=candidate_identity,
+        amount_ore=amount_ore,
+        verdict_id=verdict_id,
+        provenance=stamp(approver="ekspert", experiment="fase1-sim", timestamp=_TS),
+    )
+
+
+def _mixed_ledger() -> SavingsLedger:
+    """>=2 projects, >=2 dimensions, one cross-dimension overlap (the same candidate ``c-a`` realized
+    under both ``energi`` and ``asfalt`` in P1 -> counted ONCE by the deduped total, FLAGGED)."""
+    led = SavingsLedger()
+    led.add_realized(_entry("P1", "c-a", 1000, dimension="energi"))
+    led.add_realized(_entry("P1", "c-a", 1000, dimension="asfalt"))  # overlap: same candidate id
+    led.add_realized(_entry("P1", "c-b", 2500, dimension="energi"))
+    led.add_realized(_entry("P2", "c-c", 4000, dimension="energi"))
+    return led
+
+
+def test_build_value_report_matches_ledger_accessors() -> None:
+    """SC1: per-project + portfolio totals equal the ledger accessors; ``overlaps`` equals
+    ``ledger.overlaps()`` (the cross-dimension overlap counted ONCE, flagged)."""
+    led = _mixed_ledger()
+    report = build_value_report(led)
+
+    for pid in {e.project_id for e in led.entries}:
+        assert report.per_project[pid] == led.per_project_total(pid)
+    assert report.portfolio_total_ore == led.portfolio_total()
+    assert report.overlaps == led.overlaps()
+    # overlap counted once: P1 = c-a (1000, once across 2 dims) + c-b (2500) = 3500
+    assert report.per_project["P1"] == 3500
+    assert report.per_project["P2"] == 4000
+    assert report.overlaps == [("P1", "c-a")]
+
+
+def test_provenance_line_per_entry_verbatim_and_deterministic() -> None:
+    """SC1 (Revision #9): ``.provenance`` carries one ``ProvenanceLine`` per ledger entry with
+    verbatim ``verdict_id`` + ``provenance`` string, deterministically ordered."""
+    led = _mixed_ledger()
+    report = build_value_report(led)
+
+    assert len(report.provenance) == len(led.entries)
+    for line in report.provenance:
+        assert isinstance(line, ProvenanceLine)
+
+    by_key = {(m.project_id, m.dimension, m.candidate_identity): m for m in report.provenance}
+    for e in led.entries:
+        line = by_key[(e.project_id, e.dimension, e.candidate_identity)]
+        assert line.verdict_id == e.verdict_id  # verbatim, never re-minted
+        assert line.provenance == e.provenance  # entry's own string, no verdict-store join
+        assert line.amount_ore == e.amount_ore
+
+    # deterministically ordered: same entries in a different insertion order -> identical provenance
+    shuffled = SavingsLedger(entries=list(reversed(led.entries)))
+    assert build_value_report(shuffled).provenance == report.provenance