Subject: [PATCH v3 0/4] approxidate: tweak special date formats

From: Tuomas Ahola <[email-masked]>
Date: Thu, 14 May 2026 14:55:16 +0300

The approxidate system is an endless source of absurdities.  Let's make the
usual "eh, that's crazy, let's do better with this input" type of fix[1], and
tweak some sharp edge cases, including one noticed by Linus back in 2006[2].

After this series, "tea" and "noon" will work predictably with all kinds of
date formats (today, yesterday, last Friday, January 5th, one year ago
yesterday...) regardless of the current time of day.

Links:
  1. https://lore.kernel.org/git/[email-masked]/
  2. https://lore.kernel.org/git/[email-masked]/

Tuomas Ahola (4):
  t0006: add support for approxidate test date adjustment
  approxidate: alias "today" to "now"
  approxidate: make "specials" respect fixed day-of-month
  approxidate: use deferred mday adjustments for "specials"

 date.c          | 36 ++++++++++++++++++++++++++----------
 t/t0006-date.sh | 41 ++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 66 insertions(+), 11 deletions(-)

Intervall-diff mot v2:
1:  118f1825ac < -:  ---------- t0006: add support for approxidate test date adjustment
2:  21c4858c47 < -:  ---------- approxidate: make "specials" respect fixed day-of-month
-:  ---------- > 1:  7ea9c9967b t0006: add support for approxidate test date adjustment
-:  ---------- > 2:  3a21727dbe approxidate: alias "today" to "now"
-:  ---------- > 3:  d1992d23d0 approxidate: make "specials" respect fixed day-of-month
3:  cf72403102 ! 4:  0b1a10305c approxidate: use deferred mday adjustments for "specials"
    @@ date.c: static void pending_number(struct tm *tm, int *num)
     +static void date_time(struct tm *tm, int hour)
      {
      	/*
    - 	 * By default, "tea" and "noon" refer to last such time in the
    - 	 * past, be it today or yesterday.  With a specified mday,
    --	 * that logic is overridden.
    -+	 * or e.g. "noon today", that logic is overridden.
    + 	 * If we do not yet have a specified day, we'll use the most recent
    + 	 * version of "hour" relative to now.  But that may be yesterday.
      	 */
      	if (tm->tm_mday < 0 && tm->tm_hour < hour)
     -		update_tm(tm, now, 24*60*60);
    @@ t/t0006-date.sh
     @@ t/t0006-date.sh: check_approxidate '3:00' '2009-08-30 03:00:00'
      check_approxidate '15:00' '2009-08-30 15:00:00'
      check_approxidate 'noon today' '2009-08-30 12:00:00'
    - check_approxidate 'today at noon' '2009-08-30 12:00:00' success -12
    -+check_approxidate 'noon today' '2009-09-01 12:00:00' success +36
    + check_approxidate 'today at noon' '2009-08-30 12:00:00' '-12 hours'
    ++check_approxidate 'noon today' '2009-09-01 12:00:00' '+36 hours'
      check_approxidate 'noon yesterday' '2009-08-29 12:00:00'
      check_approxidate 'last Friday at noon' '2009-08-28 12:00:00'
    - check_approxidate 'last Friday at noon' '2009-08-28 12:00:00' success -12
    -+check_approxidate 'noon yesterday' '2009-08-29 12:00:00' success -12
    + check_approxidate 'last Friday at noon' '2009-08-28 12:00:00' '-12 hours'
    ++check_approxidate 'noon yesterday' '2009-08-29 12:00:00' '-12 hours'
     +check_approxidate 'tea last saturday' '2009-08-29 17:00:00'
    -+check_approxidate 'tea last saturday' '2009-08-29 17:00:00' success -12
    ++check_approxidate 'tea last saturday' '2009-08-29 17:00:00' '-12 hours'
      check_approxidate 'January 5th noon pm' '2009-01-05 12:00:00'
    - check_approxidate 'January 5th noon pm' '2009-01-05 12:00:00' success -12
    + check_approxidate 'January 5th noon pm' '2009-01-05 12:00:00' '-12 hours'
      check_approxidate '10am noon' '2009-08-29 12:00:00'

base-commit: c44beea485f0f2feaf460e2ac87fdd5608d63cf0
-- 
2.30.2