def test_unset_removes_assignment(self):
# Arrange
variable_name = 'A'
assignment = Assignment()
assignment.set(variable_name, 10)
# Act
assignment.unset(variable_name)
# Assert
self.assertEqual(0, assignment.count())
self.assertFalse(assignment.is_set(variable_name))
self.assertIsNone(assignment.get(variable_name))
def test_set_adds_assignment(self):
# Arrange
assignment = Assignment()
variable_name = 'A'
variable_value = 10
# Act
assignment.set(variable_name, variable_value)
# Assert
self.assertEqual(1, assignment.count())
self.assertTrue(assignment.is_set(variable_name))
self.assertEqual(variable_value, assignment.get(variable_name))
