OpenMC/tests/unit_tests/test_config.py
GuySten 00edc77691
Change test order to run unit tests first. (#3533)
Co-authored-by: Paul Romano <paul.k.romano@gmail.com>
2025-08-30 03:39:46 +00:00

104 lines
3.8 KiB
Python

from collections.abc import Mapping
import os
from pathlib import Path
import openmc
from openmc.config import _default_config
from openmc.data import decay
import pytest
@pytest.fixture(autouse=True, scope='function')
def reset_config_and_env():
"""A fixture to ensure each test has a clean config, env, and CWD."""
original_env = dict(os.environ)
original_cwd = os.getcwd()
original_resolve_paths = openmc.config["resolve_paths"]
# Reset environment variables that affect config
for key in ['OPENMC_CROSS_SECTIONS', 'OPENMC_MG_CROSS_SECTIONS', 'OPENMC_CHAIN_FILE']:
if key in os.environ:
del os.environ[key]
# Re-initialize the global config object
openmc.config = _default_config()
try:
yield
finally:
# Restore environment, CWD and resolve_paths
os.environ.clear()
os.environ.update(original_env)
os.chdir(original_cwd)
# Restore config one last time for safety between modules
openmc.config = _default_config(resolve_paths=original_resolve_paths)
def test_config_basics():
assert isinstance(openmc.config, Mapping)
with pytest.warns(UserWarning):
openmc.config['cross_sections'] = '/path/to/cross_sections.xml'
del openmc.config['cross_sections']
assert 'cross_sections' not in openmc.config
assert 'OPENMC_CROSS_SECTIONS' not in os.environ
with pytest.raises(KeyError, match="Unrecognized config key: nuke"):
openmc.config['nuke'] = '/like/to/eat/bacon'
with pytest.raises(TypeError):
openmc.config['resolve_paths'] = 'not a bool'
def test_config_path_resolution(tmp_path):
"""Test path resolution logic."""
os.chdir(tmp_path)
relative_path = Path("some/file.xml")
absolute_path = relative_path.resolve()
# Test with resolve_paths = True (default)
with pytest.warns(UserWarning):
openmc.config['cross_sections'] = relative_path
assert openmc.config['cross_sections'] == absolute_path
assert openmc.config['cross_sections'].is_absolute()
# Test with resolve_paths = False
with openmc.config.patch('resolve_paths', False):
with pytest.warns(UserWarning):
openmc.config['chain_file'] = relative_path
assert openmc.config['chain_file'] == relative_path
assert not openmc.config['chain_file'].is_absolute()
assert openmc.config['resolve_paths'] is True
def test_config_patch(tmp_path):
file_a = tmp_path / "a.xml"; file_a.touch()
file_b = tmp_path / "b.xml"; file_b.touch()
openmc.config['cross_sections'] = file_a
with openmc.config.patch('cross_sections', file_b):
assert openmc.config['cross_sections'] == file_b.resolve()
assert openmc.config['cross_sections'] == file_a.resolve()
def test_config_set_envvar(tmp_path):
"""Test that setting config also sets environment variables correctly."""
os.chdir(tmp_path)
relative_path = Path("relative.xml")
with pytest.warns(UserWarning):
openmc.config['cross_sections'] = relative_path
expected_path = str(relative_path.resolve())
assert os.environ['OPENMC_CROSS_SECTIONS'] == expected_path
def test_config_warning_nonexistent_path(tmp_path):
"""Test that a warning is issued for a path that does not exist."""
bad_path = tmp_path / "a/path/that/does/not/exist.xml"
with pytest.warns(UserWarning, match=f"Path '{bad_path}' does not exist."):
openmc.config['chain_file'] = bad_path
def test_config_chain_side_effect(tmp_path):
"""Test that modifying chain_file clears decay data caches."""
chain_file = tmp_path / "chain.xml"; chain_file.touch()
decay._DECAY_ENERGY['U235'] = (1.0, 2.0)
decay._DECAY_PHOTON_ENERGY['PU239'] = {}
openmc.config['chain_file'] = chain_file
assert not decay._DECAY_ENERGY and not decay._DECAY_PHOTON_ENERGY