Re: [PATCH v2 2/4] t-reftable-readwrite: use free_names() instead of a for loop

From: Chandra Pratap <chandrapratap3519@gmail.com>
Date: Aug 10, 2024, 05:50 UTC
Message-ID: <CA+J6zkSHX892NoNOyTDc-38_giBR=Q-Hf7+7nymU9GnPu1V-5Q@mail.gmail.com>
In-Reply-To: <xmqqjzgpcymq.fsf@gitster.g>

On Sat, 10 Aug 2024 at 00:27, Junio C Hamano <gitster@pobox.com> wrote:

Show 36 quoted lines

>
> Chandra Pratap <chandrapratap3519@gmail.com> writes:
>
> > free_names() as defined by reftable/basics.{c,h} frees a NULL
> > terminated array of malloced strings along with the array itself.
> > Use this function instead of a for loop to free such an array.
>
> Going back to [1/4], the headers included in this test looked like this:
>
>     -#include "system.h"
>     -
>     -#include "basics.h"
>     -#include "block.h"
>     -#include "blocksource.h"
>     -#include "reader.h"
>     -#include "record.h"
>     -#include "test_framework.h"
>     -#include "reftable-tests.h"
>     -#include "reftable-writer.h"
>     +#include "test-lib.h"
>     +#include "reftable/reader.h"
>     +#include "reftable/blocksource.h"
>     +#include "reftable/reftable-error.h"
>     +#include "reftable/reftable-writer.h"
>
> I found this part a bit curious, perhaps because I was not involved
> in either reftable/ or unit-tests/ development.  So I may be asking
> a stupid question, but is it intended that some headers like
> "block.h" and "record.h" are no longer included?
>
> It is understandable that inclusion of "test-lib.h" is new (and
> needs to be there to work as part of t/unit-tests/), and the leading
> directory name "reftable/" added to header files are also justified,
> of course.  But if you depend on "basics.h" and do not include it,
> that does not sound like the most hygenic thing to do, at least to
> me.

I think 'basics.{c,h}' in reftable/ is equivalent to 'stdio.h' in a generic C program, it holds fundamental functionalities to be used by other reftable structures and hence, is always (implicitly or explicitly) #included in almost all of the files in reftable/.

This test is supposed to focus on reftable's read-write functionalities so it makes sense to explicitly #include only those headers that are directly responsible for those functionalities, namely 'reader.h', 'blocksource.h' and 'reftable-writer.h'. 'reftable-error.h' is thrown in there as well because some tests need to explicitly mention the various error codes and it doesn't make sense to rely on it being #included by others.

Show 8 quoted lines

> The code changes themselves look good; I can see that the
> implementation of free_names() in reftable/basics.c safely replaces
> these loops.  There is a slight behaviour difference that names[]
> that was fed to reftable_iterator_seek_ref() earlier goes away
> before the iterator is destroyed, but _seek_ref() does not retain
> the names[0] argument in the iterator object, so that is OK.
>
> Thanks.