"""Tests for src/pygui/backend/wafer_layouts.py."""
import pytest
from pygui.backend.wafer_layouts import load_layout, available_families
from pygui.backend.zwafer_models import Sensor


def test_lists_bundled_families():
    fams = available_families()
    assert "aep" in fams and "x" in fams


def test_loads_sensors_in_mm():
    sensors = load_layout("aep")
    assert sensors and all(isinstance(s, Sensor) for s in sensors)
    assert any(s.x < 0 for s in sensors)
    assert max(abs(s.x) for s in sensors) < 200.0


def test_unknown_family_raises():
    with pytest.raises(KeyError):
        load_layout("nope")