From: Fabian Stelzer <fs@gigacodes.de>
Date: Wed, 17 Nov 2021 09:05:26 GMT
Subject: Re: [PATCH 1/2] test-lib: show missing prereq summary
Message-ID: <20211117090526.ldy5eonhbdgo2nyo@fs>
In-Reply-To: <xmqqpmqz42kj.fsf@gitster.g>

On 17.11.2021 00:19, Junio C Hamano wrote:
>Fabian Stelzer <fs@gigacodes.de> writes:
>
>> On 15.11.2021 18:44, Ævar Arnfjörð Bjarmason wrote:
>>>
>>>On Mon, Nov 15 2021, Fabian Stelzer wrote:
>>>
>>>> +if test -n "$missing_prereq"
>>>> +then
>>>> +	unique_missing_prereq=$(
>>>> +		echo $missing_prereq |
>>>> +		tr -s "," "\n" |
>>>> +		grep -v '^$' |
>>>> +		sort -u |
>>>> +		paste -s -d ',')
>>>
>>>What is paste? Some out-of-tree debugging utility?
>>>
>>>I think you might find a better way to do this shown in my
>>>"ab/generate-command-list" topic, currently in seen. It removed most of
>>>the same sort of tr|grep|sort etc. chain in generate-cmdlist.sh.
>>
>> I've looked at the generate-command-list code and TBH i still think this
>> is a better solution. If I read your change correctly you've removed the
>> sort and unique completely since it was not necessary for the use-case.
>> In this case i think it is. Since we call tr with `-s` the grep -v might
>> not be strictly necessary though. Also in this case these commands are
>> only called once at the end of the test run and not in any kind of loop
>> like in the cmdlist code so i think this variant is much easier to read
>> and debug with a negligible performance impact.
>
>I tend to agree with you.  The snippet we see above is quite
>straight-forward not over-engineered.
>
>> I tried writing a sh only variant and this is what i came up with. Not
>> sure if this could be much more simplified. It looses the sort though.
>
>Fun, but I'd rather not go there, unless this is a performance
>critical bit, which it is not.
>
>Thanks.
>

Ok, i've sent an update fixing the commit msg typo and with \012 instead
of \n. Even if might not be an issue it won't hurt.

Thanks