def test_validate_with_invalide_input_value(self):
     model = StackViewModel()
     model.set_input_value('f')
     self.assertEqual('disabled', model.is_input_button_enable())
 def test_default_enable_input_button(self):
     model = StackViewModel()
     self.assertEqual('disabled', model.is_input_button_enable())
 def test_validate_with_valide_input_value(self):
     model = StackViewModel()
     model.set_input_value(5)
     self.assertEqual('normal', model.is_input_button_enable())