Re: [PATCH v2 3/5] repo_read_index: clear SKIP_WORKTREE bit from files present in worktree

["Ævar Arnfjörð Bjarmason" <avarab@gmail.com>]

On Fri, Jan 14 2022, Elijah Newren via GitGitGadget wrote:

> From: Elijah Newren <newren@gmail.com>
> [...]
>  	# Set up a strange condition of having a file edit
> -	# outside of the sparse-checkout cone. This is just
> -	# to verify that sparse-checkout and sparse-index
> -	# behave the same in this case.
> +	# outside of the sparse-checkout cone. We want to verify
> +	# that all modes handle this the same, and detect the
> +	# modification.
>  	write_script edit-content <<-\EOF &&
> -	mkdir folder1 &&
> +	mkdir -p folder1 &&
>  	echo content >>folder1/a
>  	EOF
> -	run_on_sparse ../edit-content &&
> +	run_on_all ../edit-content &&

The end-state of this series will pass its tests with this on top, only
the last "mkdir -p" you added for the ls-files test seems to do
anything:

diff --git a/t/t1092-sparse-checkout-compatibility.sh b/t/t1092-sparse-checkout-compatibility.sh
index 2a04b532f91..160c119e17d 100755
--- a/t/t1092-sparse-checkout-compatibility.sh
+++ b/t/t1092-sparse-checkout-compatibility.sh
@@ -639,7 +639,7 @@ test_expect_success 'update-index modify outside sparse definition' '
 	# condition in which a `skip-worktree` enabled, outside-of-cone file
 	# exists on disk. It is used here to ensure `update-index` is stable
 	# and behaves predictably if such a condition occurs.
-	run_on_sparse mkdir -p folder1 &&
+	run_on_sparse mkdir folder1 &&
 	run_on_sparse cp ../initial-repo/folder1/a folder1/a &&
 	run_on_all ../edit-contents folder1/a &&
 
@@ -665,7 +665,7 @@ test_expect_success 'update-index --add outside sparse definition' '
 	EOF
 
 	# Create folder1, add new file
-	run_on_sparse mkdir -p folder1 &&
+	run_on_sparse mkdir folder1 &&
 	run_on_all ../edit-contents folder1/b &&
 
 	# The *untracked* out-of-cone file is added to the index because it does
@@ -949,7 +949,7 @@ test_expect_success 'checkout-index outside sparse definition' '
 
 	run_on_sparse rm -rf folder1 &&
 	echo test >new-a &&
-	run_on_sparse mkdir -p folder1 &&
+	run_on_sparse mkdir folder1 &&
 	run_on_all cp ../new-a folder1/a &&
 
 	test_all_match test_must_fail git checkout-index --ignore-skip-worktree-bits -- folder1/a &&
@@ -996,7 +996,7 @@ test_expect_success 'clean' '
 	test_all_match git commit -m "ignore bogus files" &&
 
 	run_on_sparse mkdir folder1 &&
-	run_on_all mkdir -p deep/untracked-deep &&
+	run_on_all mkdir deep/untracked-deep &&
 	run_on_all touch folder1/bogus &&
 	run_on_all touch folder1/untracked &&
 	run_on_all touch deep/untracked-deep/bogus &&

A bit nit-y I guess, but I do think tests are much easier to follow when
it's clear when we're doing initial setup v.s. using already set-up
data. In this case 

More importantnly I think between this and 19a0acc83e4 (t1092: test
interesting sparse-checkout scenarios, 2021-01-23) that introduced this
pattern there's a large foot-gun being left in place here by using these
"run_on_all" and "run_on_sparse" helpers to run POSIX tooling, as
opposed to git itself.

Utilities like "mv", "rm", "mkdir" etc. are differently chatty between
platform, and this helper captures their stdout/stderr for a later
test_cmp.

Now, I think actually there isn't a bug *now* because we clobber the
output, and seem to only call test_all_match() and other test_cmp
helpers right after we've run "git", not these POSIX utilities.

But since all we want in those cases is just a "run these commands in
these N dirs" it would be good to split up the helper.