This work changes the behavior of asking for a multi-valued config key to
return an empty list instead of a NULL value. This simplifies the handling
of the result and is safer for development in the future.

This is based on v4 of my unregister series [1]

[1]
https://lore.kernel.org/git/pull.1358.v4.git.1664287021.gitgitgadget@gmail.com/

This idea came about due to a bug in the git maintenance unregister work
where the result from git_config_get_value_multi() was sent directly to
for_each_string_list_item() without checking for a NULL value first.

I'm sending this as an RFC mostly because I'm not 100% sure this shift is
worth the refactoring pain and effort. I personally think getting an empty
list is a safer choice, but I can also understand if someone has a different
opinion.

Thanks, -Stolee

Derrick Stolee (5):
  config: relax requirements on multi-value return
  *: relax git_configset_get_value_multi result
  config: add BUG() statement instead of possible segfault
  config: return an empty list, not NULL
  *: expect a non-NULL list of config values

 builtin/for-each-repo.c     |  8 --------
 builtin/gc.c                | 20 ++++++++------------
 builtin/log.c               | 10 ++++------
 builtin/pack-objects.c      |  3 ---
 builtin/repack.c            | 13 +++++--------
 builtin/submodule--helper.c |  4 ++--
 config.c                    | 15 ++++++++++-----
 config.h                    |  6 +++---
 pack-bitmap.c               |  3 ---
 submodule.c                 |  2 +-
 t/helper/test-config.c      |  4 ++--
 versioncmp.c                |  8 ++++----
 12 files changed, 39 insertions(+), 57 deletions(-)

base-commit: 73a262cdca46a45aeeda6f47ea3357aaeb937e7b

Submitted-As: https://lore.kernel.org/git/pull.1369.git.1664287711.gitgitgadget@gmail.com