"""Tests for SessionInsights in src/type_aliases.py

Per-aggregate dataclass regression-guard for the metadata_promotion_20260624 track.

CONVENTION: 1-space indentation. NO COMMENTS.
"""
from __future__ import annotations

from dataclasses import FrozenInstanceError

import pytest

from src.type_aliases import SessionInsights


def test_constructor_with_kwargs() -> None:
 si = SessionInsights(total_tokens=1000, call_count=5, burn_rate=2.5)
 assert si.total_tokens == 1000
 assert si.call_count == 5
 assert si.burn_rate == 2.5


def test_field_access() -> None:
 si = SessionInsights(session_cost=0.42, completed_tickets=3, efficiency=0.85)
 assert si.session_cost == 0.42
 assert si.completed_tickets == 3
 assert si.efficiency == 0.85


def test_frozen_raises_on_mutation() -> None:
 si = SessionInsights()
 with pytest.raises(FrozenInstanceError):
  si.total_tokens = 100


def test_to_dict_roundtrip() -> None:
 si = SessionInsights(total_tokens=100, call_count=2, burn_rate=1.5, session_cost=0.5, completed_tickets=3, efficiency=0.9)
 d = si.to_dict()
 assert d["total_tokens"] == 100
 assert d["call_count"] == 2
 assert d["efficiency"] == 0.9


def test_default_values() -> None:
 si = SessionInsights()
 assert si.total_tokens == 0
 assert si.call_count == 0
 assert si.burn_rate == 0.0
 assert si.session_cost == 0.0
 assert si.completed_tickets == 0
 assert si.efficiency == 0.0


def test_hashability() -> None:
 si = SessionInsights(total_tokens=10)
 assert hash(si) is not None