On Tue, May 04 2021, Junio C Hamano wrote: > Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx> writes: > >> Is there any portability reason to avoid "local" in the porcelains? I >> don't have any plans for using it, but I don't see why we'd explicitly >> forbid it. > > Things that are not even in POSIX are forbidden unless explicitly > allowed. > > In general, he way we encouraged people to think has been "don't use > it, it is not even in POSIX" and "even if it is in POSIX, we know > the support by platform/implementation X is broken, so let's not use > it". It has been successfully helped us to stay out of portability > troubles. > > There may be a few tiny cases where we said "practically everybody > we care about has it, even though it is not in POSIX, and it makes > our life so vastly be better" to explicitly allow some feature, > though. > > And "local"? Not absolutely essential, unless you are doing a > library that you want to avoid stepping on users' toes. Besides, we > are no longer adding scripted Porcelains left and right---rather, > people are actively rewriting them. [You mailed me off-list with "Did I forget to say it is not even POSIX?", I had this reply to that, also applicable here]: BEGIN QUOTE I'm aware that it's not in POSIX. What I'm getting at is that anyone who doesn't support this must have been failing t0000-basic.sh since 01d3a526ad9 (t0000: check whether the shell supports the "local" keyword, 2017-10-26), released with v2.16.0. And all tests of any kind since 78dc08875cd (test-lib: allow short options to be bundled, 2020-03-22), perhaps earlier, I didn't trace the full includes, but that's the first use in test-lib.sh itself. Released with v2.27.0. >From my own cross-platform testing and us not having any reports about this I very much suspect that this is one of those not-in-POSIX but in practice supported everywhere, or at least anywhere Git has been ported to. So just saying it's OK to use unconditionally of "in t/?" should be fine, like e.g. some of the C89-plus-XYZ features. END QUOTE Afterwards it occurred to me that your stance on in-tree *.sh goes against e.g. brian's opinion on it expressed in reply to [1], i.e. that we might justify future new *.sh built-ins. In any case, as noted above I really don't care much about using "local" in any *.sh built-in. I just don't think this "We do not use it in scripted Porcelains[...]" clause is needed at all. It's effectively synonymous with saying "we still want to support git on platforms that are so broken they can't even run a single test in our test suite". 1. https://lore.kernel.org/git/patch-1.1-83266f30b67-20210417T084346Z-avarab@xxxxxxxxx/
