'Check that C{_ignoreErrors} actually causes errors to be ignored.'

def test_ignoreErrors(self):

    self.observer._ignoreErrors(ZeroDivisionError)
    f = makeFailure()
    self.observer.gotEvent({'message': (), 'time': time.time(), 'isError': 1, 'system': '-', 'failure': f, 'why': None})
    self.assertEqual(self.observer.getErrors(), [])
