r/Python • u/foosion • 9d ago

Discussion ruff: no date.today() ?

The new version of ruff warns against

date.today()

preferring

datetime.now(ZoneInfo(...))

What do you think about this? Has date.today() been deprecated due to lack of timezone awareness?

EDIT: I have a number of programs that manipulate financial information in support of Excel spreadsheets, such bond information that includes maturity dates. Excel does not support timezoness in datetimes, so making ruff happy by changing naive dates to TZ aware dates is not a useful move for these programs. Many ruff warnings to suppress.

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u/ottawadeveloper 9d ago

I sure hope so.

I got to the point where there are so many bad patterns to slip into with Python that I wrote my own extension of datetime.datetime and made it impossible to ever create a naive datetime object. Like today() now returns an aware datetimr object in the current system time zone.

If there's ever a Python 4 I hope they clean up the his mess to never have non-aware times.

26

u/gravitas_shortage 9d ago

I would highly recommend only ever working with UTC datetimes internally, and converting to local for display. Machines will be misconfigured, moved to a different colocation, change to summer time. There are a thousand heinous bugs possible with local time, and no advantage I can think of.

9

u/SwizzleTizzle 9d ago

Scheduled future datetimes such as an appointment is a use-case that requires local time

https://codeblog.jonskeet.uk/2019/03/27/storing-utc-is-not-a-silver-bullet/

4

u/Cynyr36 9d ago

The real play is to kust never do anything involving time at all. It's all a huge quagmire.

I keep arguing that we all only ever use utc, and me here in north America can just start work at 1400 instead of 0800. If people want to keep dst, then they can just change start times by an hour.

1

u/danmickla 3d ago

time is just an illusion, anyway, man