def test_change_constants(self):
volatile = frozenset('b')
volatile_dict = FrozenDict(b=ExpressionScalar('b'))
ds = DictScope(FrozenDict({'a': 1, 'b': 2}), volatile=volatile)
changes = {'b': 3, 'c': 4}
ds2 = ds.change_constants(changes)
self.assertEqual({'a': 1, 'b': 2}, dict(ds))
self.assertEqual(volatile_dict, ds.get_volatile_parameters())
self.assertEqual({'a': 1, 'b': 3}, dict(ds2))
self.assertEqual(volatile_dict, ds2.get_volatile_parameters())
with self.assertWarns(NonVolatileChange):
ds.change_constants({'a': 2, 'b': 3, 'c': 4})
def test_get_volatile(self):
volatile = frozenset('ab')
volatile_dict = FrozenDict(a=ExpressionScalar('a'), b=ExpressionScalar('b'))
ds = DictScope(FrozenDict({'a': 1, 'b': 2}), volatile=volatile)
self.assertEqual(volatile_dict, ds.get_volatile_parameters())
