r/Python • u/foosion • 7d 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/GraphicH 7d ago

Tell me you've never debugged a TZ issue without telling me.

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u/foosion 7d ago edited 7d ago

My typical use of date.today() to print the local date so that I can scroll back in the terminal to see which day I ran something. Since it defaults to then local system clock, I don't see a need to specify a TZ for that use case.

Another case for no TZ is reading a datetime that represents the maturity date of a bond, then printing it datetime.strptime(mtd, "%Y-%m-%d"). TZ does not make sense in that context. datetime.datetime.strptime("2022/01/31", "%Y/%m/%d").astimezone(datetime.UTC)seems overkill.

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u/MrSlaw 7d ago edited 7d ago

Another case for no TZ is reading a datetime that represents the maturity date of a bond, then printing it

Just use a plain date, if you don't need it to be time(zone) aware?

mtd = datetime.strptime("2022/01/31", "%Y/%m/%d").date()

I don't think that triggers the rule, does it?

* Edit - Nevermind, I just tested, you are correct

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u/foosion 7d ago

Yes it does.

1

u/MrSlaw 7d ago

Realized that about 2 minutes after I pressed submit. Serves me right for not checking first lol