tests/runtime/test_session_distance.py

import proteus.game.scenarios  # noqa: F401
from proteus.game.engine.difficulty import Difficulty
from proteus.providers import FakeProvider
from proteus.game.agents import VanillaAgent
from proteus.game.runtime import SessionRunner


def test_each_turn_records_pre_and_post_bfs_distance():
    prov = FakeProvider(["ACTION: up"] * 10, model_name="demo")
    trace = SessionRunner(
        "template", VanillaAgent(prov), difficulty=Difficulty.EASY,
        seed=42, play_turns=4, use_probe=False,
    ).run()
    for t in trace.turns:
        assert t.pre_bfs_distance is not None
        assert t.post_bfs_distance is not None
        assert t.post_focal_pos is not None
    # spec §9: away-move quality is measured vs the PRE-move predator cell
    first = trace.turns[0]
    assert first.agent_distance_delta is not None


def test_episode_records_turn_order_capture_rule_horizon():
    prov = FakeProvider(["ACTION: up"] * 10, model_name="demo")
    trace = SessionRunner(
        "template", VanillaAgent(prov), difficulty=Difficulty.EASY,
        seed=42, play_turns=4, use_probe=False,
    ).run()
    assert trace.turn_order == "focal_then_predator"
    assert trace.capture_rule == "same_cell"
    assert trace.horizon == 4