def test_get_config():
class SubConfig(Config):
pass
config = Config({'a': {'b': {'c': 1}}})
sub_config_a = config.get_config('a')
assert isinstance(sub_config_a, Config)
assert not isinstance(sub_config_a, SubConfig)
sub_config_b = config.get_config('a', config_class=SubConfig)
assert isinstance(sub_config_b, Config)
assert isinstance(sub_config_b, SubConfig)
sub_config_c = sub_config_b.get_config('b')
assert isinstance(sub_config_c, Config)
assert not isinstance(sub_config_c, SubConfig)
def test_sub_config_does_not_mutate_parent_config():
config = Config({'a': {'b': {'c': 1}}})
assert 'a.b.d' not in config
sub_config = config.get_config('a.b')
sub_config['d'] = 2
assert 'a.b.d' not in config
