Re: [RFC/PATCH 2/2] Testing the new code

From: Junio C Hamano <gitster@pobox.com>
Date: Aug 3, 2015, 19:47 UTC
Message-ID: <xmqqoaio888d.fsf@gitster.dls.corp.google.com>
In-Reply-To: <CAGZ79kYBvQ9vfmDNs2_WTLU0OrHShS7_fLnjHgYxX9C29PdDsA@mail.gmail.com>

Stefan Beller <sbeller@google.com> writes:

Show 22 quoted lines

> On Fri, Jul 31, 2015 at 6:02 PM, Junio C Hamano <gitster@pobox.com> wrote:
>> Stefan Beller <sbeller@google.com> writes:
>>
>>> -module_list()
>>> +module_list_shell()
>>>  {
>>>       eval "set $(git rev-parse --sq --prefix "$wt_prefix" -- "$@")"
>>>       (
>>> @@ -187,6 +187,29 @@ module_list()
>>>       '
>>>  }
>>>
>>> +module_list()
>>> +{
>>> +     # call both the old and new code
>>> +     module_list_shell $@ >/u/git_submodule_module_list_shell 2>/u/git_submodule_module_list_shell2
>>> +     git submodule--helper --module_list $@ >/u/git_submodule_module_list 2>/u/git_submodule_module_list2
>>
>> You seem to be discarding the double-quote around $@ in both of
>> these two places.  Intended?
>
> No, not at all. This was a bit sloppy.

OK.

> This patch was rather showing off how I intend to test the previous patch.

Yeah, I can see what the code is doing, and you already saw that I didn't disagree with the approach ;). During a reimplementation exercise, it often is a good idea, if the code structure allows you to, to run both implementations and compare the results---but it can go only so far. It obviously is tricky to apply the trick to an operation that is not idempotent to let two implementations to do it twice in different ways and make sure they produce the same result.