This test how deep we can recurse, and that we get an exception when we do, as opposed to a stack overflow. On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". PASS msg is 'RangeError: Maximum call stack size exceeded.' PASS msg is 'RangeError: Maximum call stack size exceeded.' PASS msg is 'RangeError: Maximum call stack size exceeded.' PASS msg is 'RangeError: Maximum call stack size exceeded.' PASS successfullyParsed is true TEST COMPLETE