Hi Eric,

On 04.12.20 19:06, Eric Sunshine wrote:

On Fri, Dec 4, 2020 at 10:25 AM Peter Kaestle [off-list ref] wrote:

quoted

[...]
Furthermore a regression test case is added, which tests for recursive
fetches on a superproject with uninitialized sub repositories.  This
issue was leading to an infinite loop when doing a revert of a62387b.

Just a few small comments (nothing comprehensive) from a quick scan of
the patch...

Mostly they are just minor style issues, not necessarily worth a
re-roll, but there is one actionable item.

thanks for your comments.  A new patch will follow soon.

quoted

Signed-off-by: Peter Kaestle <redacted>
---

diff --git a/t/t5526-fetch-submodules.sh b/t/t5526-fetch-submodules.sh

@@ -719,4 +719,98 @@ test_expect_success 'fetch new submodule commit intermittently referenced by sup
+add_commit_push () {
+       dir="$1"
+       msg="$2"
+       shift 2

We typically recommend including these assignments in the &&-chain to
future-proof against someone later inserting code above them and not
realizing that that code is not part of the &&-chain, in which case if
the new code fails, the failure might go unnoticed.

ok

quoted

+       git -C "$dir" add "$@" &&
+       git -C "$dir" commit -a -m "$msg" &&
+       git -C "$dir" push
+}
+
+compare_refs_in_dir () {
+       fail= &&
+       if test "x$1" = 'x!'
+       then
+               fail='!' &&
+               shift
+       fi &&
+       git -C "$1" rev-parse --verify "$2" >expect &&
+       git -C "$3" rev-parse --verify "$4" >actual &&
+       eval $fail test_cmp expect actual
+}

We have a test_cmp_rev() similar to this but it doesn't support -C as
some of our other test functions do. I briefly wondered if it would
make sense to extend it to understand -C, but even that wouldn't help
this case since compare_refs_in_dir() introduced here involves two
distinct directories. The need here is so special-purpose that it
likely would not make sense to upgrade test_cmp_rev() to accommodate
it. Okay.

Yes, I saw that there's a similar function and I tried to modify this 
one first.  Unfortunately this didn't work without touching much 
unaffected test code.  So I propose to continue with this additional 
function.

quoted

+test_expect_success 'setup nested submodule fetch test' '
+       # does not depend on any previous test setups
+
+       for repo in outer middle inner
+       do
+               (
+                       git init --bare $repo &&
+                       git clone $repo ${repo}_content &&
+                       echo "$repo" >"${repo}_content/file" &&
+                       add_commit_push ${repo}_content "initial" file
+               ) || return 1
+       done &&

What is the purpose of the subshell here? Is it to ensure that commits
in each repo have identical timestamps? Or is it just for making the
&& and || expression more clear? If the latter, we normally don't
bother with the parentheses.

It was intended to make the correlation of && and || clear.  I have 
experienced many cases in the past where things were screwed because it 
was not clearly understood by everybody.  I'll propose next patch 
without this subshell.

quoted

+       git clone outer A &&
+       git -C A submodule add "$pwd/middle" &&
+       git -C A/middle/ submodule add "$pwd/inner" &&
+       add_commit_push A/middle/ "adding inner sub" .gitmodules inner &&
+       add_commit_push A/ "adding middle sub" .gitmodules middle &&
+
+       git clone outer B &&
+       git -C B/ submodule update --init middle &&
+
+       compare_refs_in_dir A HEAD B HEAD &&
+       compare_refs_in_dir A/middle HEAD B/middle HEAD &&
+       test -f B/file &&
+       test -f B/middle/file &&
+       ! test -f B/middle/inner/file &&

These days we typically use test_path_exists() (or
test_path_is_file()) and test_path_is_missing() rather than bare
`test`.

ok.

quoted

+test_expect_success 'setup recursive fetch with uninit submodule' '
+       # does not depend on any previous test setups
+
+       git init main &&
+       git init sub &&
+
+       touch sub/file &&

Unless the timestamp of the file is significant to the test, in which
case `touch` is used, we normally create empty files like this:

     >sub/file &&

ok.

quoted

+test_expect_success 'recursive fetch with uninit submodule' '
+       git -C main submodule deinit -f sub &&
+       ! git -C main fetch --recurse-submodules |&
+               grep -v -m1 "Fetching submodule sub$" &&

We want the test scripts to be portable, thus avoid Bashisms such as `|&`. > We also avoid placing a Git command upstream in a pipe since doing so
causes the exit code of the Git command to be lost. Instead, we would
normally send the Git output to a file and then send that file to
whatever would be downstream of the Git command in the pipe. So, a
mechanical rewrite of the above (without thinking too hard about it)
might be:

     git -C main fetch --recurse-submodules >out 2>&1 &&
     ! grep -v -m1 "Fetching submodule sub$" &&

In general I agree, but for this special test case, it's required to 
have the two commands connected by a pipe, as the grep needs to kill the 
git call in error case.  Otherwise for this regression git would go for 
an infinite recursion loop.

Of course, we can go for a "git 2>&1 | grep" solution.

quoted

+       git -C main submodule status |
+               sed -e "s/^-//" -e "s/ sub$//" >actual &&

Same comment about avoiding Git upstream in a pipe, so perhaps:

     git -C main submodule status >out &&
     sed -e "s/^-//" -e "s/ sub$//" out >actual &&

quoted

+       test_cmp expect actual
+'

ok.

-- 
kind regards
--peter;