dir: synchronize treat_leading_path() and read_directory_recursive()

Our optimization to avoid calling into read_directory_recursive() when
all pathspecs have a common leading directory mean that we need to match
the logic that read_directory_recursive() would use if we had just
called it from the root.  Since it does more than call treat_path() we
need to copy that same logic.

Alternatively, we could try to change treat_path to return path_recurse
for an untracked directory under the given special circumstances that
this logic checks for, but a simple switch results in many test failures
such as 'git clean -d' not wiping out untracked but empty directories.
To work around that, we'd need the caller of treat_path to check for
path_recurse and sometimes special case it into path_untracked.  In
other words, we'd still have extra logic in both places.

Needing to duplicate logic like this means it is guaranteed someone will
eventually need to make further changes and forget to update both
locations.  It is tempting to just nuke the leading_directory special
casing to avoid such bugs and simplify the code, but unpack_trees'
verify_clean_subdirectory() also calls read_directory() and does so with
a non-empty leading path, so I'm hesitant to try to restructure further.
Add obnoxious warnings to treat_leading_path() and
read_directory_recursive() to try to warn people of such problems.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/t/t3011-common-prefixes-and-directory-traversal.sh b/t/t3011-common-prefixes-and-directory-traversal.sh
index 098fddc75b..3da5b2b6e7 100755
--- a/t/t3011-common-prefixes-and-directory-traversal.sh
+++ b/t/t3011-common-prefixes-and-directory-traversal.sh
@@ -195,7 +195,7 @@ test_expect_success 'git ls-files -o consistent between one or two dirs' '
 
 # ls-files doesn't have a way to request showing both untracked and ignored
 # files at the same time, so use `git status --ignored`
-test_expect_failure 'git status --ignored shows same files under dir with or without pathspec' '
+test_expect_success 'git status --ignored shows same files under dir with or without pathspec' '
 	cat <<-EOF >expect &&
 	?? an_untracked_dir/
 	!! an_untracked_dir/ignored