Not getting a negative duration from datediff when I reversed the two dates

[tinker2much]

I expected the second one to give a negative duration.

pi@pi0w:~/bin $ dateutils.ddiff 2024-09-26T18:00:00-05:00 2024-09-26T19:33:07-0500  -f '%Y years %m months %w weeks %d days %H hours %M minutes %S seconds'
0 years 0 months 0 weeks 0 days 1 hours 33 minutes 7 seconds

pi@pi0w:~/bin $ dateutils.ddiff 2024-09-26T19:33:07-0500 2024-09-26T18:00:00-0500  -f '%Y years %m months %w weeks %d days %H hours %M minutes %S seconds'
0 years 0 months 0 weeks 0 days 1 hours 33 minutes 7 seconds