Resetting time to 00:00:00.0

[rimutaka]

It takes too many lines to do a simple and commonly used (at least in my case) operation:

let x = dt.with_hour(0).unwrap().with_minute(0).unwrap().with_second(0).unwrap();

Is there a simpler way of achieving the same?

if not, would you consider a PR to do a reset like that in a single step? E.g.

let x = dt.reset_time();

[esheppa]

Thanks for the question @rimutaka - one possible option is to do:

let x = NaiveTime::MIN;

This works as of e7d4402 and will be released in 0.4.23 but can currently be accessed on branch 0.4.x.

[rimutaka]

@esheppa , Eric, sorry, I probably miss something important here.

Is there a way to replace the time only portion in DateTime<Tz> with NaiveTime::MIN as you suggested?

I have an immutable var with DateTime<Tz>, say let x = Utc::now();. I need to reset the time portion of that to zeros, e.g. let y = x.reset_time(); or x.with_time(NaiveTime::MIN);.

• x: 2023-01-03T23:19:08.281426984+00:00
• y: 2023-01-03T00:00:00.0+00:00

And I need to do it often enough in my code to find the current multi-step approach of resetting hr, min, sec, ns too verbose.

[rimutaka]

@esheppa , Eric, I submitted a draft PR for this feature under #930 . Can you or any other maintainers take a look before I spend any more time polishing it?

Unrelated: the pipeline has a step with cargo clippy --color=always -- -D warnings -A clippy::manual-non-exhaustive, but there are no warnings related to clippy::manual-non-exhaustive. Should that option be removed?

[rimutaka]

Looks like the simplest way of resetting the time for DateTime<Tz> is this:

let x = dt_w_tz.date_naive()
        .and_time(NaiveTime::MIN)
        .and_local_timezone(x.timezone())
        .unwrap();

The maintainers looked into my PR #930 to simplify this, but the gains were marginal and we would still need to use unwrap() to avoid a potential panic.