Re: [RFC PATCH v3 1/5] clone: test for our behavior on odd objects/* content

>
> Add tests for what happens when we locally clone .git/objects
> directories where some of the loose objects or packs are symlinked, or
> when when there's unknown files there.
>
> I'm bending over backwards here to avoid a SHA1 dependency. See [1]
> for an earlier and simpler version that hardcoded a SHA-1s.
>
> This behavior has been the same for a *long* time, but hasn't been
> tested for.
>
> There's a good post-hoc argument to be made for copying over unknown
> things, e.g. I'd like a git version that doesn't know about the
> commit-graph to copy it under "clone --local" so a newer git version
> can make use of it.
>
> But the behavior showed where with symlinks seems pretty
> random. E.g. if "pack" is a symlink we end up with two copies of the
> contents, and only transfer some symlinks as-is.
>
> In follow-up commits we'll look at changing some of this behavior, but
> for now let's just assert it as-is so we'll notice what we'll change
> later.
>
> 1. https://public-inbox.org/git/20190226002625.13022-5-avarab@gmail.com/
>
> Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
> ---
>  t/t5604-clone-reference.sh | 142 +++++++++++++++++++++++++++++++++++++
>  1 file changed, 142 insertions(+)
>
> diff --git a/t/t5604-clone-reference.sh b/t/t5604-clone-reference.sh
> index 4320082b1b..cb0dc22d14 100755
> --- a/t/t5604-clone-reference.sh
> +++ b/t/t5604-clone-reference.sh
> @@ -221,4 +221,146 @@ test_expect_success 'clone, dissociate from alternates' '
>         ( cd C && git fsck )
>  '
>
> +test_expect_success 'setup repo with garbage in objects/*' '
> +       git init S &&
> +       (
> +               cd S &&
> +               test_commit A &&
> +
> +               cd .git/objects &&
> +               >.some-hidden-file &&
> +               >some-file &&
> +               mkdir .some-hidden-dir &&
> +               >.some-hidden-dir/some-file &&
> +               >.some-hidden-dir/.some-dot-file &&
> +               mkdir some-dir &&
> +               >some-dir/some-file &&
> +               >some-dir/.some-dot-file
> +       )
> +'
> +
> +test_expect_success 'clone a repo with garbage in objects/*' '
> +       for option in --local --no-hardlinks --shared --dissociate
> +       do
> +               git clone $option S S$option || return 1 &&
> +               git -C S$option fsck || return 1
> +       done &&
> +       find S-* -name "*some*" | sort >actual &&
> +       cat >expected <<-EOF &&
> +       S--dissociate/.git/objects/.some-hidden-file
> +       S--dissociate/.git/objects/some-dir
> +       S--dissociate/.git/objects/some-dir/.some-dot-file
> +       S--dissociate/.git/objects/some-dir/some-file
> +       S--dissociate/.git/objects/some-file
> +       S--local/.git/objects/.some-hidden-file
> +       S--local/.git/objects/some-dir
> +       S--local/.git/objects/some-dir/.some-dot-file
> +       S--local/.git/objects/some-dir/some-file
> +       S--local/.git/objects/some-file
> +       S--no-hardlinks/.git/objects/.some-hidden-file
> +       S--no-hardlinks/.git/objects/some-dir
> +       S--no-hardlinks/.git/objects/some-dir/.some-dot-file
> +       S--no-hardlinks/.git/objects/some-dir/some-file
> +       S--no-hardlinks/.git/objects/some-file
> +       EOF
> +       test_cmp expected actual
> +'
> +
> +test_expect_success SYMLINKS 'setup repo with manually symlinked objects/*' '
> +       git init T &&
> +       (
> +               cd T &&
> +               test_commit A &&
> +               git gc &&
> +               (
> +                       cd .git/objects &&
> +                       mv pack packs &&
> +                       ln -s packs pack
> +               ) &&
> +               test_commit B &&
> +               (
> +                       cd .git/objects &&
> +                       find ?? -type d >loose-dirs &&
> +                       last_loose=$(tail -n 1 loose-dirs) &&
> +                       mv $last_loose a-loose-dir &&
> +                       ln -s a-loose-dir $last_loose &&
> +                       first_loose=$(head -n 1 loose-dirs) &&
> +                       (
> +                               cd $first_loose &&
> +                               obj=$(ls *) &&
> +                               mv $obj ../an-object &&
> +                               ln -s ../an-object $obj
> +                       ) &&
> +                       find . -type f | sort >../../../T.objects-files.raw &&
> +                       find . -type l | sort >../../../T.objects-links.raw
> +               )
> +       ) &&
> +       git -C T fsck &&
> +       git -C T rev-list --all --objects >T.objects
> +'
> +
> +
> +test_expect_success SYMLINKS 'clone repo with symlinked objects/*' '
> +       for option in --local --no-hardlinks --shared --dissociate
> +       do
> +               git clone $option T T$option || return 1 &&
> +               git -C T$option fsck || return 1 &&
> +               git -C T$option rev-list --all --objects >T$option.objects &&
> +               test_cmp T.objects T$option.objects &&
> +               (
> +                       cd T$option/.git/objects &&
> +                       find . -type f | sort >../../../T$option.objects-files.raw &&
> +                       find . -type l | sort >../../../T$option.objects-links.raw
> +               )
> +       done &&
> +
> +       for raw in $(ls T*.raw)
> +       do
> +               sed -e "s!/..\$!/X!; s!/../!/Y/!; s![0-9a-f]\{38,\}!Z!" <$raw >$raw.de-sha || return 1
> +       done &&
> +
> +       cat >expected-files <<-EOF &&
> +       ./Y/Z
> +       ./a-loose-dir/Z
> +       ./an-object
> +       ./Y/Z
> +       ./info/packs
> +       ./loose-dirs
> +       ./pack/pack-Z.idx
> +       ./pack/pack-Z.pack
> +       ./packs/pack-Z.idx
> +       ./packs/pack-Z.pack
> +       EOF
> +       cat >expected-links <<-EOF &&
> +       ./Y/Z
> +       EOF
> +       for option in --local --dissociate
> +       do
> +               test_cmp expected-files T$option.objects-files.raw.de-sha || return 1 &&
> +               test_cmp expected-links T$option.objects-links.raw.de-sha || return 1
> +       done &&
> +
> +       cat >expected-files <<-EOF &&
> +       ./Y/Z
> +       ./Y/Z
> +       ./a-loose-dir/Z
> +       ./an-object
> +       ./Y/Z
> +       ./info/packs
> +       ./loose-dirs
> +       ./pack/pack-Z.idx
> +       ./pack/pack-Z.pack
> +       ./packs/pack-Z.idx
> +       ./packs/pack-Z.pack
> +       EOF
> +       test_cmp expected-files T--no-hardlinks.objects-files.raw.de-sha &&
> +       test_must_be_empty T--no-hardlinks.objects-links.raw.de-sha &&
> +
> +       cat >expected-files <<-EOF &&
> +       ./info/alternates
> +       EOF
> +       test_cmp expected-files T--shared.objects-files.raw &&
> +       test_must_be_empty T--shared.objects-links.raw
> +'
> +
>  test_done
> --
> 2.21.0.rc2.261.ga7da99ff1b
>