GNU bug report logs - #33892
guix package --list-generations uses UTC and time-at-midnight for hour durations

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Date: Fri, 28 Dec 2018 10:31:20 +0100
From: "pelzflorian (Florian Pelz)" <pelzflorian@HIDDEN>
To: bug-guix@HIDDEN
Subject: guix package --list-generations uses UTC and time-at-midnight for
 hour durations
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Hello Guix,

I would expect guix package --list-generations=3D=E2=80=A6h to display
generations from the past =E2=80=A6 hours, but apparently it displays
generations offset from UTC midnight (apparently not local time?) and
not the current time, since guix/ui.scm calls a procedure named
time-at-midnight.

In particular, when `guix package --list-generations` shows

Generation 38	Dec 15 2018 13:04:16	(current)

then I would expect

$ date --date=3D"Dec 15 2018 13:04:16" +%s
1544875456
$ date +%s
1545989113
$ guix package --list-generations=3D$(((1545989113-1544875456)/3600+1))h

to display the current generation.

I think either the time for hours should not be computed from midnight
and should use local time for days/weeks.  Alternatively, the
description in the manual should be adjusted.

Regards,
Florian