Re: [PATCH 1/5] t7300: add testcase showing unnecessary traversal into ignored directory

[Eric Sunshine <sunshine@sunshineco.com>]

On Fri, May 7, 2021 at 1:01 AM Elijah Newren <newren@gmail.com> wrote:
> On Thu, May 6, 2021 at 9:27 PM Eric Sunshine <sunshine@sunshineco.com> wrote:
> > Is this expensive/slow loop needed because you'd otherwise run afoul
> > of command-line length limits on some platforms if you tried creating
> > the entire mess of directories with a single `mkdir -p`?
>
> The whole point is creating a path long enough that it runs afoul of
> limits, yes.
>
> If we had an alternative way to check whether dir.c actually recursed
> into a directory, then I could dispense with this and just have a
> single directory (and it could be named a single character long for
> that matter too), but I don't know of a good way to do that.  (Some
> possiibilities I considered along that route are mentioned at
> https://lore.kernel.org/git/CABPp-BF3e+MWQAGb6ER7d5jqjcV=kYqQ2stM_oDyaqvonPPPSw@mail.gmail.com/)

Thanks, I read that exchange (of course) immediately after sending the
above question.

> > > +               while test ! -f directory-random-file.txt; do
> > > +                       name=$(ls -d directory*) &&
> > > +                       mv $name/* . &&
> > > +                       rmdir $name
> > > +               done
> >
> > Shouldn't this cleanup loop be under the control of
> > test_when_finished() to ensure it is invoked regardless of how the
> > test exits?
>
> I thought about that, but if the test fails, it seems nicer to leave
> everything behind so it can be inspected.  It's similar to test_done,
> which will only delete the $TRASH_DIRECTORY if all the tests passed.
> So no, I don't think this should be under the control of
> test_when_finished.

I may be confused, but I'm not following this reasoning. If you're
using `-i` to debug a failure within the test, then the
test_when_finished() cleanup actions won't be triggered anyhow
(they're suppressed by `-i`), so everything will be left behind as
desired.

The problem with not placing this under control of
test_when_finished() is that, if something in the test proper does
break, after the "test failed" message, you'll get the undesirable
alpine-linux-musl behavior you explained in your earlier email where
test_done() bombs out.