Subject: Re: [PATCH v2 6/8] t7063: drop non-POSIX argument "-ls" from find(1)

From: Danh Doan <[email-masked]>
Date: Mon, 23 Mar 2020 22:11:49 +0700

On 2020-03-23 15:11:50+0100, Johannes Schindelin <[email-masked]> wrote:
> Hi,
> 
> On Sun, 22 Mar 2020, Đoàn Trần Công Danh wrote:
> 
> > Since commit 6b7728db81, (t7063: work around FreeBSD's lazy mtime
> > update feature, 2016-08-03), we started to use ls as a trick to update
> > directory's mtime.
> >
> > However, `-ls` flag isn't required by POSIX's find(1), and
> > busybox(1) doesn't implement it.
> >
> > >From the original conversation, it seems like find(1) with "-type d"
> > could trigger enough "lstat(2)" to ask FreeBSD update mtime.
> 
> This rationale  makes me uneasy: why did Duy add _both_ `-type d` *and*
> `-ls` if the former would have been enough?
> 
> > Use only filter "-type d" for now.
> >
> > Signed-off-by: Đoàn Trần Công Danh <[email-masked]>
> > ---
> >  t/t7063-status-untracked-cache.sh | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/t/t7063-status-untracked-cache.sh b/t/t7063-status-untracked-cache.sh
> > index 190ae149cf..6791c6b95a 100755
> > --- a/t/t7063-status-untracked-cache.sh
> > +++ b/t/t7063-status-untracked-cache.sh
> > @@ -18,7 +18,7 @@ GIT_FORCE_UNTRACKED_CACHE=true
> >  export GIT_FORCE_UNTRACKED_CACHE
> >
> >  sync_mtime () {
> > -	find . -type d -ls >/dev/null
> > +	find . -type d >/dev/null
> 
> A more conservative patch would be the following:
> 
> -- snip --
> commit 1680a64fae24b1073dbf1b844889a9953823b7a2
> Author: Johannes Schindelin <[email-masked]>
> Date:   Wed Jul 19 22:13:16 2017 +0200
> 
>     t7063: when running under BusyBox, avoid unsupported find option
> 
>     BusyBox' find implementation does not understand the -ls option, so
>     let's not use it when we're running inside BusyBox.

Yes, this patch is a conservative patch.
In v1, I went with "-exec ls -dils {} +".

And, Jeff worries about a lot of flags passed to ls may run into
compatibility issue.

> 
>     Signed-off-by: Johannes Schindelin <[email-masked]>
> 
> diff --git a/t/t7063-status-untracked-cache.sh
> b/t/t7063-status-untracked-cache.sh
> index 190ae149cf3c..ab7e8b5fea01 100755
> --- a/t/t7063-status-untracked-cache.sh
> +++ b/t/t7063-status-untracked-cache.sh
> @@ -18,7 +18,12 @@ GIT_FORCE_UNTRACKED_CACHE=true
>  export GIT_FORCE_UNTRACKED_CACHE
> 
>  sync_mtime () {
> -       find . -type d -ls >/dev/null
> +       if test_have_prereq BUSYBOX
> +       then
> +               find . -type d -print0 | xargs -0r ls -ld >/dev/null

Can we just change back to what Duy proposed time ago:

	find . -type d -exec ls -ld {} \;

> +       else
> +               find . -type d -ls >/dev/null
> +       fi
>  }
> 
>  avoid_racy() {
> -- snap --
> 
> I have this in Git for Windows' fork, although I have to admit that there
> is no CI set up to verify that this is all working as I expect it to.

I'd find some time (later) to setup a Travis build with Alpine and VoidLinux,
mainly for musl check.

-- 
Danh