public void Check_WhenTemperatureIsLowerAndHeaterIsNotStarted_ShouldStartHeater()
{
_currentTemperatureProvider.Stub(x => x.GetTemperature()).Return(19);
_temperatureSettingsProvider.Stub(x => x.GetRequestedTemperature()).Return(20);
_thermostat.Check();
_heater.AssertWasCalled(x => x.Start());
}