fixes#10455
@KAAtheWiseGit, I'm sorry, I didn't mean to block your first PR #10461,
didn't see you had submitted it till I got around to submitting this. If
you want to incoporate useful ideas from this PR into yours, I do not
mind deferring to you.
# Description
Changes made in `datetime-diff`:
* Initialize millisecond and microsecond fields in `$current`, to fix
the error when borrow needs to refer to them.
* Fix `borrow_nanoseconds` to borrow from seconds, not from (unused)
microseconds.
* Added error check to insist that first argument is >= second argument.
`datetime-diff` doesn't represent negative durations correctly (it tries
to borrow out of the year, resulting in negative year and positive all
other fields). We don't currently have a use case requiring negative
durations.
* Add comments so help is a bit clearer (I was surprised that the first
argument, named `$from` was actually supposed to be the *later*
datetime. The order of arguments is reasonable (reminiscent of <later>
<minus> <earlier>), so I just changed the param name to match its
purpose.
Changes made in `pretty-print-duration`:
* changed type of argument from `duration` to `record`. (it's not clear
why Nu was not complaining about this!)
* changed test for skipping a clause from `> 0` to `!= 0`. Even though
`datetime-diff` won't present a negative field in the record, user might
call `pretty-print-duration` with one, might as well handle it. (but I
think `hour:-2` will be rendered as `-2hr`, not `-2hrs`...).
* added help and an example.
# User-Facing Changes
none requiring code changes.
# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`
-
- # After Submitting
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