def METHOD_NAME(self):
    l1 = self.router.local()
    service = self.klass(self.router)
    service.register_prefix('/etc')
    pool = mitogen.service.Pool(
        router=self.router,
        services=[service],
        size=1,
    )
    path = '/etc/foo/bar/../../../passwd'
    try:
        e = self.assertRaises(mitogen.core.CallError,
            lambda: l1.call(
                mitogen.service.FileService.get,
                context=self.router.myself(),
                path=path,
                out_fp=None,
            )
        )
    finally:
        pool.stop()
    expect = service.unregistered_msg % (path,)
    self.assertIn(expect, e.args[0])