def METHOD_NAME(self, entries, errors, options_map):
    """
      2013-05-18 * ""
        Assets:Investments:MSFT      -10 MSFT {-200.00 USD}
        Assets:Investments:Cash  2000.00 USD
    """
    booked_entries, booking_errors = booking.book(entries, options_map)
    self.assertEqual(1, len(entries))
    self.assertEqual(1, len(booking_errors))
    self.assertRegex(booking_errors[0].message, 'Cost is negative')