Re: [PATCH] p3400: stop using tac(1)

["René Scharfe" <l.s.r@web.de>]

Am 05.10.21 um 21:38 schrieb Jeff King:
> On Tue, Oct 05, 2021 at 08:45:38PM +0200, René Scharfe wrote:
>
>> Am 04.10.21 um 10:31 schrieb Jeff King:
>>> On Sat, Oct 02, 2021 at 07:44:14PM +0200, René Scharfe wrote:
>>>
>>>> b3dfeebb92 (rebase: avoid computing unnecessary patch IDs, 2016-07-29)
>>>> added a perf test that calls tac(1) from GNU core utilities.  Support
>>>> systems without it by reversing the generated list using sort -nr
>>>> instead.  sort(1) with options -n and -r is already used in other tests.
>>>
>>> Cute fix. With regular seq(1), this whole thing can become:
>>>
>>>   seq 1000 -1 1
>>>
>>> without the extra process, but our test_seq doesn't understand non-1
>>> increments (nor comparisons besides -le). It wouldn't be that hard to
>>> teach it, but given that this is the first time we've wanted it, it may
>>> not be worth the effort.
>>
>> Right.  The original also allows "seq 1000 1", by the way.  Not sure we
>> need that either.
>
> I'm not sure what you mean by "original" here. "seq 1000 1" produces no
> output for me (nor does it work with test_seq).

I meant the non-shell one, i.e. seq(1).  I somehow expected everyone to use
the same, but of course there is GNU seq, which has "an omitted INCREMENT
defaults to 1 even when LAST is smaller than FIRST" [1] and BSD seq with
"When first is larger than last the default incr is -1" [2].

[1] https://www.man7.org/linux/man-pages/man1/seq.1.html
[2] https://man.netbsd.org/seq.1

René