The default time format is changed after localization date support

[zwpaper]

after merging #820, the default time format is changed,
maybe we should switch back to the previous format, and add a flag for the localization date.

cc @meain

[meain]

Yup, we should stick to original format. Changing the defaults is a bad idea. Maybe add another option to --date flag, maybe something like locale?

[zwpaper]

@scarf005 do you have some cycle to look into this?

[scarf005]

is the upper section of the screenshot before #820 and the lower section of the screenshot after #820?
in the PR i've changed val.format("%c").to_string() to val.format_localized("%c", locale).to_string(), this could've been the cause of the regression. I'm not sure why the same format works differently, however.

[zwpaper]

@scarf005 it may be the difference between localed time format or not.

So if we could add the localed format under a option, that would be great.

[scarf005]

is DateFlag::Date for default format and DateFlag::Formatted for user defined formatting?
if so, maybe we could replace "%c" with "%a %b %d %T %Y" to simulate previous behavior.

scarf@TG02:~$ LANG=c date +"%a %b %d %T %Y"
Sat Apr 15 22:09:51 2023

[zwpaper]

scarf@TG02:~$ LANG=c date +"%a %b %d %T %Y"
Sat Apr 15 22:09:51 2023

this seems to be a good solution for this, but like the --time-style=locale(https://man7.org/linux/man-pages/man1/ls.1.html) in GNU ls, maybe we should also better provide a locale value to date option, and opt-in locale instead of locale by default.

[scarf005]

https://github.com/coreutils/coreutils/blob/cc95246ee2ed674cd407f0f80fd77f3364012458/src/ls.c#L2397-L2404
looks like GNU coreutils default --time-style to locale.

I do agree that providing --time-style is a good idea, but a pointer on how to make implement it would be very helpful. for example

• how to add --time-style flag
• how should it handle formatting style from config file (code-wise)

[zwpaper]

oh, I have not noticed that the locale is the default! then we could align to it.

how to add --time-style flag

we would now stick to the date flag, and migrate to time-style later, that would be not much change needed.

how should it handle formatting style from config file (code-wise)

how about:

        if let Date::Date(val) = self {
            match &flags.date {
				// leave this to not localized
                DateFlag::Date => val.format_localized("%c", locale).to_string(),
				// add a Locale and format with "%a %b %d %T %Y" to simulate the previous format with locale support
                DateFlag::Relative => HumanTime::from(*val - Local::now()).to_string(),
                DateFlag::Iso => {
                    // 365.2425 * 24 * 60 * 60 = 31556952 seconds per year
                    // 15778476 seconds are 6 months
                    if *val > Local::now() - Duration::seconds(15_778_476) {
                        val.format("%m-%d %R").to_string()
                    } else {
                        val.format("%F").to_string()
                    }
                }
                DateFlag::Formatted(format) => val.format_localized(format, locale).to_string(),

[zwpaper]

close as fixed by #840