test-driver/tests/selfverification/test_self_verification.py

"""The framework's foundational guarantees, verified from outside the framework.

These read an Evidence Pack the way an auditor would — as JSON, with no live
objects — and use plain pytest. No Oracle, no Runner, no Verdict aggregation.
"""

from __future__ import annotations

import json

import pytest

from testdriver import Runner
from scenarios.alice_bob_carol import USE_CASE, build
from tests.selfverification.checks import (
    SELF_CHECKS,
    check_actor_isolation,
    check_evidence_supports_every_verdict,
    check_intent_independence,
    check_no_actor_collected_judgment,
    check_runs_agree,
    check_verdicts_follow_from_judgment_evidence,
)

SECRETS = {
    "alice": "alice-only-9f3c",
    "bob": "bob-only-2a71",
    "carol": "carol-only-55e0",
}


def run_and_serialize(*mutations: str):
    """Run, then throw away everything except the serialized evidence.

    Deliberate: the checks must work from the artefact alone, exactly as they
    would months later, with no access to the objects that produced it.
    """
    world, driver, observer, asset, oracle = build(*mutations)
    for actor_id, secret in SECRETS.items():
        world.cast[actor_id].remember("private", secret)
    result = Runner(world, driver, observer, oracle).run(asset)
    pack = json.loads(result.evidence.to_json())
    memories = {a.id: {k: a.recall(k) for k in a.known_keys()} for a in world.cast}
    return pack, memories, list(world.cast.actors)


def test_the_registry_is_complete():
    assert len(SELF_CHECKS) == 4


# --- td://self/actor-isolation -------------------------------------------


def test_actor_isolation():
    pack, memories, _ = run_and_serialize()
    assert check_actor_isolation(pack, SECRETS, memories) == []


# --- td://self/oracle-independence ---------------------------------------


def test_no_actor_collected_judgment_evidence():
    pack, _, actors = run_and_serialize()
    assert check_no_actor_collected_judgment(pack, actors) == []


@pytest.mark.parametrize("mutations", [(), ("M15",), ("M11",), ("M01", "M15")])
def test_verdicts_are_reproducible_from_judgment_evidence_alone(mutations):
    """Holds on passing and failing runs alike — a check that only works when
    everything is green is not verifying independence, it is verifying luck."""
    pack, _, _ = run_and_serialize(*mutations)
    assertions = list(USE_CASE.claims) + list(USE_CASE.invariants)
    assert check_verdicts_follow_from_judgment_evidence(pack, assertions) == []


# --- td://self/evidence-reproducibility -----------------------------------


def test_every_verdict_is_supported_by_retained_evidence():
    pack, _, _ = run_and_serialize()
    assert check_evidence_supports_every_verdict(pack) == []


def test_two_runs_from_the_same_seed_agree():
    first, _, _ = run_and_serialize()
    second, _, _ = run_and_serialize()
    assert check_runs_agree(first, second) == []
    assert first["run_id"] != second["run_id"]


def test_reproducibility_holds_on_a_failing_run():
    first, _, _ = run_and_serialize("M15")
    second, _, _ = run_and_serialize("M15")
    assert check_runs_agree(first, second) == []
    assert any(v["verdict"] == "FAIL" for v in first["verdicts"])


# --- td://self/intent-independence ----------------------------------------


def test_intent_independence():
    pack, _, _ = run_and_serialize()
    assert check_intent_independence(pack) == []


def test_intent_independence_holds_when_a_claim_fails():
    """The moment that matters: a FAIL is an accusation, and an accusation
    resting on implementation-derived intent is worthless."""
    pack, _, _ = run_and_serialize("M15")
    assert check_intent_independence(pack) == []