def test_power_integer(self):
        """
        Test 0 ** -1.
        Note 2 ** <big number> returns an undefined value (depending
        on the algorithm).
        """
        dtype = np.int64
        f = vectorize(["int64(int64, int64)"], nopython=True)(power)
        a = np.array([5, 0, 6], dtype=dtype)
        b = np.array([1, -1, 2], dtype=dtype)
        expected = np.array([5, -2**63, 36], dtype=dtype)
        with self.check_warnings([]):
            res = f(a, b)
            self.assertPreciseEqual(res, expected)

        Test 0 ** -1.
        Note 2 ** <big number> returns an undefined value (depending
        on the algorithm).
        
numba/tests/npyufunc/test_errors.py