test intervals - test nanoseconds 1980-12-12 12:12:12.123456789 1980-12-12 12:12:12.123456700 1980-12-12 12:12:12.123456789 1930-12-12 12:12:12.123456789 1930-12-12 12:12:12.123456700 2220-12-12 12:12:12.123456789 2220-12-12 12:12:12.123456700 - test microseconds 1980-12-12 12:12:12.123456 1980-12-12 12:12:12.123400 1980-12-12 12:12:12.123456 1980-12-12 12:12:12.123456 1930-12-12 12:12:12.123456 1930-12-12 12:12:12.123400 1930-12-12 12:12:12.123456 2220-12-12 12:12:12.123456 2220-12-12 12:12:12.123400 2220-12-12 12:12:12.123456 - test milliseconds 1980-12-12 12:12:12.123 1980-12-12 12:12:12.120 1980-12-12 12:12:12.123 1980-12-12 12:12:12.123 1930-12-12 12:12:12.123 1930-12-12 12:12:12.120 1930-12-12 12:12:12.123 2220-12-12 12:12:12.123 2220-12-12 12:12:12.120 2220-12-12 12:12:12.123 test add[...]seconds() - test nanoseconds 1980-12-12 12:12:12.123456790 1980-12-12 12:12:12.123456701 1980-12-12 12:12:12.123456790 1930-12-12 12:12:12.123456790 1930-12-12 12:12:12.123456701 2220-12-12 12:12:12.123456790 2220-12-12 12:12:12.123456701 - test microseconds 1980-12-12 12:12:12.123457 1980-12-12 12:12:12.123401 1980-12-12 12:12:12.12345778 1980-12-12 12:12:12.123457 1930-12-12 12:12:12.123457 1930-12-12 12:12:12.123401 1930-12-12 12:12:12.12345778 2220-12-12 12:12:12.123457 2220-12-12 12:12:12.123401 2220-12-12 12:12:12.12345778 - test milliseconds 1980-12-12 12:12:12.124 1980-12-12 12:12:12.121 1980-12-12 12:12:12.124456 1980-12-12 12:12:12.124 1930-12-12 12:12:12.124 1930-12-12 12:12:12.121 1930-12-12 12:12:12.124456 2220-12-12 12:12:12.124 2220-12-12 12:12:12.121 2220-12-12 12:12:12.124456 test subtract[...]seconds() - test nanoseconds 2022-12-31 23:59:59.999999999 2022-12-31 23:59:59.999999900 2023-01-01 00:00:00.000000001 2023-01-01 00:00:00.000000100 - test microseconds 2022-12-31 23:59:59.999999 2022-12-31 23:59:59.999900 2023-01-01 00:00:00.000001 2023-01-01 00:00:00.000100 - test milliseconds 2022-12-31 23:59:59.999 2022-12-31 23:59:59.900 2023-01-01 00:00:00.001 2023-01-01 00:00:00.100