This tests the DST status in dates earlier than 1970-01-01 00:00 UTC. Regardless of your time zone, it should not fail. This tests time zones: US/Pacific, US/Central, US/Mountain, US/Eastern, CET, Asia/Jerusalem and NZ. On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". PASS (new Date(1970, 0, 1)).getHours() is 0 PASS (new Date(1969, 8, 1)).getHours() is 0 PASS (new Date(1969, 9, 28)).getHours() is 0 PASS successfullyParsed is true TEST COMPLETE