I just found another class of this bug that the submitted patch does
not fix. If the units are at the beginning of the string, then they are
also ignored. For example, `date 'm d y2020m11d3'` is also valid. I
think the fix here is to check and make sure that ptype is 0 before
reassigning the value to a non-zero number. I'll send an updated patch
with this tonight.
