'Test error output.'

def test_errorString(self):

    f = failure.Failure(ValueError('That    is    bad.'))
    self.lp.msg(failure=f, isError=True)
    prefix = 'CRITICAL:'
    output = self.out.getvalue()
    self.assertTrue(output.startswith(prefix), 'Does    not    start    with    {0!r}:    {1!r}'.format(prefix, output))
