core/tests/test_pack_grounding.py

"""ADR-0048 — pack-grounded fallback surface tests.

The contract these tests pin:

  - Pack-grounded surfaces engage ONLY when the ``UnknownDomainGate``
    fires with ``source="empty_vault"`` AND the intent is DEFINITION
    or RECALL AND the subject lemma is in ``en_core_cognition_v1``.
  - The surface is composed verbatim from the pack lexicon's
    ``semantic_domains`` and the lemma — no synthesis.
  - The audit contract is preserved: ChatResponse and TurnEvent both
    carry a ``grounding_source`` provenance tag set to ``"pack"`` on
    the pack-grounded path, ``"none"`` on the universal disclosure,
    and ``"vault"`` on the main walk path.
  - Safety / ethics refusal still takes priority — pack-grounded
    surfaces never bypass a SafetyVerdict violation.
"""

from __future__ import annotations

import pytest

from chat.pack_grounding import (
    PACK_ID,
    is_pack_lemma,
    pack_grounded_surface,
)
from chat.runtime import ChatRuntime, _UNKNOWN_DOMAIN_SURFACE


# ---------------------------------------------------------------------------
# pack_grounding module — pure-function contracts
# ---------------------------------------------------------------------------


@pytest.mark.parametrize("lemma", ["light", "knowledge", "meaning", "memory", "truth"])
def test_known_pack_lemmas_produce_grounded_surface(lemma: str) -> None:
    surface = pack_grounded_surface(lemma)
    assert surface is not None
    assert lemma in surface
    assert PACK_ID in surface
    assert "No session evidence yet." in surface


def test_unknown_lemma_returns_none() -> None:
    assert pack_grounded_surface("nonexistentwordxyz") is None


@pytest.mark.parametrize("bad", ["", "   ", None])
def test_empty_or_invalid_lemma_returns_none(bad) -> None:
    assert pack_grounded_surface(bad) is None  # type: ignore[arg-type]


def test_is_pack_lemma_round_trips() -> None:
    assert is_pack_lemma("light") is True
    assert is_pack_lemma("nonexistentwordxyz") is False
    assert is_pack_lemma("") is False


def test_surface_is_deterministic() -> None:
    """Same lemma must produce byte-identical surfaces on repeat calls
    — pack is immutable, no randomness, no synthesis."""
    a = pack_grounded_surface("light")
    b = pack_grounded_surface("light")
    assert a == b
    assert a is not None


# ---------------------------------------------------------------------------
# ChatRuntime integration — cold-start path
# ---------------------------------------------------------------------------


def test_cold_start_definition_returns_pack_grounded_surface() -> None:
    """Cold-start DEFINITION on a pack-known lemma routes through the
    pack-grounded surface, not the universal disclosure."""
    rt = ChatRuntime()
    resp = rt.chat("What is light?")
    assert "pack-grounded" in resp.surface
    assert "light" in resp.surface
    assert resp.grounding_source == "pack"


def test_cold_start_recall_returns_pack_grounded_surface() -> None:
    """RECALL intent on a pack-known lemma also engages the pack path."""
    rt = ChatRuntime()
    resp = rt.chat("Remember light")
    assert resp.grounding_source == "pack"
    assert "light" in resp.surface


def test_cold_start_unknown_lemma_returns_universal_disclosure() -> None:
    """When the gate fires AND the subject lemma is not in the pack,
    we fall through to the universal disclosure unchanged."""
    rt = ChatRuntime()
    # 'addresses' is in vocab but subject after intent parsing will be
    # the multi-word phrase, which won't match the pack lemma index.
    resp = rt.chat("How can I correct an error?")
    assert resp.surface == _UNKNOWN_DOMAIN_SURFACE
    assert resp.grounding_source == "none"


def test_cold_start_non_definition_intent_no_pack_grounding() -> None:
    """CAUSE / COMPARISON / VERIFICATION intents do not engage the
    pack path even when their subject is a pack lemma — narrow scope
    of ADR-0048 is DEFINITION + RECALL only."""
    rt = ChatRuntime()
    # 'Why does light exist?' is CAUSE intent.
    resp = rt.chat("Why does light exist?")
    assert resp.grounding_source == "none"
    assert resp.surface == _UNKNOWN_DOMAIN_SURFACE


def test_turn_event_carries_grounding_source() -> None:
    """ADR-0048 provenance propagates to TurnEvent for downstream audit."""
    rt = ChatRuntime()
    rt.chat("What is light?")
    last_event = rt.turn_log[-1]
    assert getattr(last_event, "grounding_source", None) == "pack"


def test_chat_response_grounding_source_default_for_main_path() -> None:
    """When the walk path runs, the ChatResponse carries
    ``grounding_source="vault"``.  We force the walk by priming the
    vault with one turn so the second turn's gate clears."""
    rt = ChatRuntime()
    rt.chat("light truth")  # seed vault with one known-token turn
    resp = rt.chat("light truth")
    # The second turn may or may not have vault hits depending on
    # gate threshold; what we assert is that grounding_source is set
    # to one of the documented values.
    assert resp.grounding_source in {"vault", "pack", "none"}


def test_pack_grounded_surface_passes_safety_check() -> None:
    """Pack-grounded surfaces preserve the audit contract — safety
    and ethics verdicts still surface and refusal still takes
    priority above pack grounding when triggered."""
    rt = ChatRuntime()
    resp = rt.chat("What is light?")
    # Safety verdict must be present on every stub-path response
    # (ADR-0035).  Specific verdict outcome depends on the safety
    # pack — we only assert the audit contract holds.
    assert resp.safety_verdict is not None
    assert resp.ethics_verdict is not None