def test_circuitbreaker_should_clear_last_exception_on_success_call():
cb = CircuitBreaker(name='Foobar')
cb._last_failure = IOError()
assert isinstance(cb.last_failure, IOError)
cb.call(lambda: True)
assert cb.last_failure is None
def test_circuitbreaker_should_save_last_exception_on_failure_call():
cb = CircuitBreaker(name='Foobar')
func = Mock(side_effect=IOError)
with raises(IOError):
cb.call(func)
assert isinstance(cb.last_failure, IOError)
def test_circuitbreaker_should_call_fallback_function_if_open():
fallback = Mock(return_value=True)
func = Mock(return_value=False)
CircuitBreaker.opened = lambda self: True
cb = CircuitBreaker(name='WithFallback', fallback_function=fallback)
cb.call(func)
fallback.assert_called_once_with()
