[GSoC][PATCH v4 0/7] t: port reftable/pq_test.c to the unit testing framework

[Chandra Pratap <chandrapratap3519@gmail.com>]

In the recent codebase update (commit 8bf6fbd, 2023-12-09), a new unit
testing framework written entirely in C was introduced to the Git project
aimed at simplifying testing and reducing test run times.
Currently, tests for the reftable refs-backend are performed by a custom
testing framework defined by reftable/test_framework.{c, h}. Port
reftable/pq_test.c to the unit testing framework and improve upon
the ported test.

The first two patches in the series are preparatory cleanup, the third patch
moves the test to the unit testing framework, and the rest of the patches
improve upon the ported test.

Mentored-by: Patrick Steinhardt <ps@pks.im>
Mentored-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Chandra Pratap <chandrapratap3519@gmail.com>

---
Changes in v4:
- Add a commit message for the second patch

CI/PR for v4: https://github.com/gitgitgadget/git/pull/1745

Chandra Pratap(7):
reftable: remove unncessary curly braces in reftable/pq.c
reftable: change the type of array indices to 'size_t' in
t: move reftable/pq_test.c to the unit testing framework
t-reftable-pq: make merged_iter_pqueue_check() static
t-reftable-pq: make merged_iter_pqueue_check() callable
t-reftable-pq: add test for index based comparison
t-reftable-pq: add tests for merged_iter_pqueue_top()

Makefile                     |   2 +-
reftable/pq.c                |  29 +++--------
reftable/pq.h                |   1 -
reftable/pq_test.c           |  74 ----------------------------
t/helper/test-reftable.c     |   1 -
t/unit-tests/t-reftable-pq.c | 155 +++++++++++++++++++++++++++++++++++++++++++++
6 files changed, 166 insertions(+), 96 deletions(-)

Range-diff against v3:
1:  3c333e7770 ! 1:  1873fb02ce reftable: change the type of array indices to 'size_t' in reftable/pq.c
    @@ Metadata
      ## Commit message ##
         reftable: change the type of array indices to 'size_t' in reftable/pq.c
     
    +    The variables 'i', 'j', 'k' and 'min' are used as indices for
    +    'pq->heap', which is an array. Additionally, 'pq->len' is of
    +    type 'size_t' and is often used to assign values to these
    +    variables. Hence, change the type of these variables from 'int'
    +    to 'size_t'.
    +
         Mentored-by: Patrick Steinhardt <ps@pks.im>
         Mentored-by: Christian Couder <chriscool@tuxfamily.org>
         Signed-off-by: Chandra Pratap <chandrapratap3519@gmail.com>
2:  bf547f705a = 2:  3cccf8266a t: move reftable/pq_test.c to the unit testing framework
3:  7dd3a2b27f = 3:  4b63849694 t-reftable-pq: make merged_iter_pqueue_check() static
4:  c803e7adfc = 4:  3698a7189f t-reftable-pq: make merged_iter_pqueue_check() callable by reference
5:  0b03f3567d = 5:  d58c8f709e t-reftable-pq: add test for index based comparison
6:  0cdfa6221e = 6:  69521f0ff7 t-reftable-pq: add tests for merged_iter_pqueue_top()