Re: [PATCH v3 10/11] t-reftable-record: add tests for reftable_ref_record_compare_name()

>
> Chandra Pratap <chandrapratap3519@gmail.com> writes:
>
> > reftable_ref_record_compare_name() is a function defined by
> > reftable/record.{c, h} and is used to compare the refname of two
> > ref records when sorting multiple ref records using 'qsort'.
> > In the current testing setup, this function is left unexercised.
> > Add a testing function for the same.
> >
> > Mentored-by: Patrick Steinhardt <ps@pks.im>
> > Mentored-by: Christian Couder <chriscool@tuxfamily.org>
> > Signed-off-by: Chandra Pratap <chandrapratap3519@gmail.com>
> > ---
> >  t/unit-tests/t-reftable-record.c | 23 +++++++++++++++++++++++
> >  1 file changed, 23 insertions(+)
> >
> > diff --git a/t/unit-tests/t-reftable-record.c b/t/unit-tests/t-reftable-record.c
> > index 55b8d03494..f45f2fdef2 100644
> > --- a/t/unit-tests/t-reftable-record.c
> > +++ b/t/unit-tests/t-reftable-record.c
> > @@ -95,6 +95,28 @@ static void test_reftable_ref_record_comparison(void)
> >       check(!reftable_record_cmp(&in[0], &in[1]));
> >  }
> >
> > +static void test_reftable_ref_record_compare_name(void)
> > +{
> > +     struct reftable_ref_record recs[14] = { 0 };
> > +     size_t N = ARRAY_SIZE(recs), i;
> > +
> > +     for (i = 0; i < N; i++)
> > +             recs[i].refname = xstrfmt("%02"PRIuMAX, (uintmax_t)i);
>
> This needs to be free'd too right?
>
> So we create an array of 14 records, with refnames "00", "01", "02" ...
> "13", here.
>
> > +
> > +     QSORT(recs, N, reftable_ref_record_compare_name);
> > +
>
> We then use `reftable_ref_record_compare_name` as the comparison
> function to sort them.
>
> > +     for (i = 1; i < N; i++) {
> > +             check_int(strcmp(recs[i - 1].refname, recs[i].refname), <, 0);
> > +             check_int(reftable_ref_record_compare_name(&recs[i], &recs[i]), ==, 0);
> > +     }
>
> Here we use `strcmp` to ensure that the ordering done by
> `reftable_ref_record_compare_name` is correct. This makes sense,
> although I would have expected this to be done the other way around.
> i.e. we should use `strcmp` as the function used in `QSORT` and in this
> loop we validate that `reftable_ref_record_compare_name` also produces
> the same result when comparing.

> > +
> > +     for (i = 0; i < N - 1; i++)
> > +             check_int(reftable_ref_record_compare_name(&recs[i + 1], &recs[i]), >, 0);
> > +
>
> Also, with the current setup, we use `reftable_ref_record_compare_name`
> to sort the first array and then use `reftable_ref_record_compare_name`
> to check if it is correct? This doesn't work, we need to isolate the
> data creation from the inference, if the same function can influence
> both, then we are not really testing the function.

> > +     for (i = 0; i < N; i++)
> > +             reftable_ref_record_release(&recs[i]);
> > +}
> > +
>
> Nit: The top three loops could possibly be combined.

> >  static void test_reftable_ref_record_roundtrip(void)
> >  {
> >       struct strbuf scratch = STRBUF_INIT;
> > @@ -490,6 +512,7 @@ int cmd_main(int argc, const char *argv[])
> >       TEST(test_reftable_log_record_comparison(), "comparison operations work on log record");
> >       TEST(test_reftable_index_record_comparison(), "comparison operations work on index record");
> >       TEST(test_reftable_obj_record_comparison(), "comparison operations work on obj record");
> > +     TEST(test_reftable_ref_record_compare_name(), "reftable_ref_record_compare_name works");
> >       TEST(test_reftable_log_record_roundtrip(), "record operations work on log record");
> >       TEST(test_reftable_ref_record_roundtrip(), "record operations work on ref record");
> >       TEST(test_varint_roundtrip(), "put_var_int and get_var_int work");
> > --
> > 2.45.2.404.g9eaef5822c