fix: .dt.time() was panicking for datetimes prior to unix epoch

[MarcoGorelli]

closes #13801

[MarcoGorelli]

this one should've been sorted to begin with, but that's already being dealt with in #13808

[MarcoGorelli]

I timed this separately, and apply_values is faster here than apply

[mcrumiller]

This is a bit more concise (I'm always looking to reduce code length) and possibly faster since it removes the if branch (although maybe a premature optimization). Also I think we're already at i64 so we can remove the extra .cast(&Int64).unwrap().

            #[cfg(feature = "dtype-time")]
            (Datetime(tu, _), Time) => Ok({
                let (modder, multiplier) = match tu {
                    TimeUnit::Nanoseconds => (NS_IN_DAY, 1i64),
                    TimeUnit::Microseconds => (US_IN_DAY, 1_000i64),
                    TimeUnit::Milliseconds => (MS_IN_DAY, 1_000_000i64),
                };
                self.0
                    .apply_values(|v| (v % modder * multiplier) + (NS_IN_DAY * (v < 0) as i64))
                    .into_time()
                    .into_series()
            }),

[ritchie46]

I thinks this is a nice improvement. @mcrumiller 👍

[MarcoGorelli]

yup - @mcrumiller fancy opening a PR to my PR, so you're included in the commit?

[mcrumiller]

Sure (although I don't care about the cred)--need to figure out how to check out a branch on another fork first.

Edit: I used git remote add <Marco's fork url> followed by a checkout of his branch. Not sure if that's the best way to do it.

[MarcoGorelli]

good learning experience then :) but yes, that's how I'd have done it

alternatively,

git checkout -b pr/marcogorelli/man-on-the-moon
git fetch marcogorelli
git reset --hard marcogorelli/man-on-the-moon
<do your changes>
git push -U marcogorelli HEAD:man-on-the-moon

[mcrumiller]

Got that working, now trying to figure out how to do create the PR, as your fork doesn't seem to show up in git's list:

[mcrumiller]

Edit: w00t

[MarcoGorelli]

the issue with the current implementation is that self.0.as_ref() % NS_IN_DAY might return a negative value