How do I make the friendly format show units bigger than days?

[azzamsa]

How to ask HumanTime to show years, month, days?
Am I missing something?

use jiff::{
    civil::Date,
    fmt::friendly::{Designator, SpanPrinter},
    Zoned,
};

fn main() -> anyhow::Result<()> {
    let date: Date = "2015-06-10".parse()?;
    let span: jiff::Span = Zoned::now().date() - date;

    println!("It has been {}", format!("{span:#}"));
    println!("It has been {}", humanize(span));

    Ok(())
}

// Turn duration into human readable format
fn humanize(span: jiff::Span) -> String {
    dbg!(span);
    let printer = SpanPrinter::new().designator(Designator::HumanTime);
    printer.span_to_string(&span)
}

🦄 cargo r`
It has been 3534d
[src/main.rs:19:5] span = 3534d
It has been 3534d

[dependencies]
jiff = "0.2"
anyhow = "1.0"

[BurntSushi]

Does the section on rounding help answer your question?

For your code, I would do it like this, by specifying the largest unit:

use jiff::{
    civil::Date,
    fmt::friendly::{Designator, SpanPrinter},
    Unit, Zoned,
};

fn main() -> anyhow::Result<()> {
    let date: Date = "2015-06-10".parse()?;
    let span = Zoned::now().date().since((Unit::Year, date))?;

    println!("It has been {}", format!("{span:#}"));
    println!("It has been {}", humanize(span));

    Ok(())
}

// Turn duration into human readable format
fn humanize(span: jiff::Span) -> String {
    let printer = SpanPrinter::new().designator(Designator::HumanTime);
    printer.span_to_string(&span)
}

Has this output:

$ cargo -q r
It has been 9y 8mo 1d
It has been 9y 8months 1d

And note that you can do this directly on Zoned:

use jiff::{civil::Date, tz::TimeZone, Unit, Zoned};

fn main() -> anyhow::Result<()> {
    let date: Date = "2015-06-10".parse()?;
    let zdt = date.to_zoned(TimeZone::system())?;
    let span = Zoned::now().date().since((Unit::Year, &zdt))?;

    println!("It has been {}", format!("{span:#}"));

    Ok(())
}

Has this output:

$ cargo -q r
It has been 9y 8mo 1d

And if you do subtraction between two zoned datetime and get "too many" units like this:

use jiff::{tz::TimeZone, Unit, Zoned};

fn main() -> anyhow::Result<()> {
    let zdt = "2015-06-10T17:30[Poland]"
        .parse::<Zoned>()?
        .with_time_zone(TimeZone::system());
    let span = Zoned::now().since((Unit::Year, &zdt))?;
    println!("It has been {}", format!("{span:#}"));

    Ok(())
}

$ cargo -q r
It has been 9y 8mo 20h 11m 33s 877ms 721µs 838ns

You can also specify the smallest unit, and Jiff will do automatic rounding for you:

use jiff::{tz::TimeZone, Unit, Zoned, ZonedDifference};

fn main() -> anyhow::Result<()> {
    let zdt = "2015-06-10T17:30[Poland]"
        .parse::<Zoned>()?
        .with_time_zone(TimeZone::system());
    let span = Zoned::now().since(
        ZonedDifference::new(&zdt).smallest(Unit::Second).largest(Unit::Year),
    )?;
    println!("It has been {}", format!("{span:#}"));

    Ok(())
}

Which gives:

$ cargo -q r
It has been 9y 8mo 20h 14m 24s

[azzamsa]

Thanks a lot for Jiff 🥞

[BurntSushi]

<3