def test_issue_868(self):
        '''
        Summary: multiplying a scalar by a non-scalar would cause a crash in
        type inference because TimeDeltaMixOp always assumed at least one of
        its operands was an NPTimeDelta in its generic() method.
        '''
        with self.assertRaises(TypingError) as raises:
            njit((types.Array(types.int32, 1, 'C'),))(issue_868)

        expected = ((_header_lead + " Function(<built-in function mul>) found "
                     "for signature:\n \n >>> mul(UniTuple({} x 1), {})")
            .format(str(types.intp), types.IntegerLiteral(2)))
        self.assertIn(expected, str(raises.exception))
        self.assertIn("During: typing of", str(raises.exception))

        Summary: multiplying a scalar by a non-scalar would cause a crash in
        type inference because TimeDeltaMixOp always assumed at least one of
        its operands was an NPTimeDelta in its generic() method.
        
numba/tests/test_typingerror.py