Patrick Steinhardt <ps@xxxxxx> writes:
> On Sun, Jan 12, 2025 at 12:11:07AM +0100, Jan Palus wrote:
>> Fixes compatibility with mksh as well:
>> $ mksh -c 'printf "%0.s" ""'
>> printf: %0.s: invalid conversion specification
>>
>> Fixes: e7fb2ca945 ("builtin/blame: fix out-of-bounds write with blank boundary commits")
>
> We don't typically use Fixes tags in our project, but instead embed the
> commit into the commit message with `git log --format=reference -1`
> together with a description.
>
> The subject can also be adjusted a bit: we use to just write the test
> number, and the important aspect is not that we simplify the padding
> generation, but that we make it more portable.
>
> So, my suggestion would be:
>
> t8002: fix unportable printf formatting directives
>
> In e7fb2ca945 (builtin/blame: fix out-of-bounds write with blank
> boundary commits, 2025-01-10), we have introduced two new tests that
> expect a certain amount of padding. This padding is generated via
> printf using the "%0.s" formatting directive. That directive is
> non-portable and not understood by for example mksh, breaking these
> tests on platforms using that shell.
>
> Fix this issue by using "%${N}s" instead, which is already being
> used in t5300 and thus portable enough for us.
Is "%.0s" really not portable, or is it just mksh
being a bit lacking?
"That directive non-portable ..." -> "Some implementations (e.g.
one that is built into mksh) does not support the precision to be 0
(i.e. "%.0" before the "s" conversion)"
Other than that, your version is easy to read and understand.
>> - $(printf "%0.s " $(test_seq 11)) (<author@xxxxxxxxxxx> 2005-04-07 15:45:13 -0700 1) abbrev
>> + $(printf "%11s" "") (<author@xxxxxxxxxxx> 2005-04-07 15:45:13 -0700 1) abbrev
>> EOF
>> git blame -b --abbrev=10 ^HEAD -- abbrev.t >actual &&
>> test_cmp expect actual
>
> Okay, makes sense. And as mentioned, we already have such a use of
> printf in t5300, so it should be portable enough for our use case.
Thanks for reviewing, and thanks, Jan, for noticing and fixing.
