[PATCH 4/4] attr.c: fix matching "subdir" without the trailing slash

["Nguyễn Thái Ngọc Duy" <pclouds@gmail.com>]

The story goes back to 94bc671 (Add directory pattern matching to
attributes - 2012-12-08). Before this commit, directories are passed
to path_matches without the trailing slash. This is fine for matching
pattern "subdir" with "foo/subdir".

Patterns like "subdir/" (i.e. match _directory_ subdir) won't work
though. So paths are now passed to path_matches with the trailing
slash (i.e. "subdir/"). The trailing slash is used as the directory
indicator (similar to dtype in exclude case). This makes pattern
"subdir/" match directory "subdir/". Pattern "subdir" no longer match
subdir, which is now "subdir/".

As the trailing slash in pathname is the directory indicator, we do
not need to keep it in the pathname for matching. The trailing slash
should be turned to dtype "DT_DIR" and stripped out of pathname. This
keeps the code pattern similar to exclude.

The same applies for the pattern "subdir/". The trailing slash is
converted to flag EXC_FLAG_MUSTBEDIR and should not remain in the
pattern, as noted in parse_exclude_pattern(). prepare_attr_stack()
breaks this and keeps the trailing slash anyway.

To sum up, both patterns and pathnames should never have the trailing
slash when it comes to match_basename.

Reported-and-analyzed-by: Jeff King <peff@peff.net>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
---
 attr.c                          | 11 +++++++++--
 t/t5002-archive-attr-pattern.sh |  6 ++++++
 2 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/attr.c b/attr.c
index 1818ba5..a95c837 100644
--- a/attr.c
+++ b/attr.c
@@ -256,7 +256,7 @@ static struct match_attr *parse_attr_line(const char *line, const char *src,
 				      &res->u.pat.flags,
 				      &res->u.pat.nowildcardlen);
 		if (res->u.pat.flags & EXC_FLAG_MUSTBEDIR)
-			res->u.pat.patternlen++;
+			p[res->u.pat.patternlen] = '\0';
 		if (res->u.pat.flags & EXC_FLAG_NEGATIVE) {
 			warning(_("Negative patterns are ignored in git attributes\n"
 				  "Use '\\!' for literal leading exclamation."));
@@ -665,9 +665,16 @@ static int path_matches(const char *pathname, int pathlen,
 {
 	const char *pattern = pat->pattern;
 	int prefix = pat->nowildcardlen;
+	int dtype;
+
+	if (pathlen && pathname[pathlen-1] == '/') {
+		dtype = DT_DIR;
+		pathlen--;
+	} else
+		dtype = DT_REG;
 
 	if ((pat->flags & EXC_FLAG_MUSTBEDIR) &&
-	    ((!pathlen) || (pathname[pathlen-1] != '/')))
+	    dtype != DT_DIR)
 		return 0;
 
 	if (pat->flags & EXC_FLAG_NODIR) {
diff --git a/t/t5002-archive-attr-pattern.sh b/t/t5002-archive-attr-pattern.sh
index 0c847fb..98ccc3c 100755
--- a/t/t5002-archive-attr-pattern.sh
+++ b/t/t5002-archive-attr-pattern.sh
@@ -27,6 +27,10 @@ test_expect_success 'setup' '
 	echo ignored-only-if-dir/ export-ignore >>.git/info/attributes &&
 	git add ignored-only-if-dir &&
 
+	mkdir -p ignored-without-slash &&
+	echo ignored without slash >ignored-without-slash/foo &&
+	git add ignored-without-slash/foo &&
+	echo ignored-without-slash export-ignore >>.git/info/attributes &&
 
 	mkdir -p one-level-lower/two-levels-lower/ignored-only-if-dir &&
 	echo ignored by ignored dir >one-level-lower/two-levels-lower/ignored-only-if-dir/ignored-by-ignored-dir &&
@@ -49,6 +53,8 @@ test_expect_exists	archive/not-ignored-dir/ignored-only-if-dir
 test_expect_exists	archive/not-ignored-dir/
 test_expect_missing	archive/ignored-only-if-dir/
 test_expect_missing	archive/ignored-ony-if-dir/ignored-by-ignored-dir
+test_expect_missing	archive/ignored-without-slash/ &&
+test_expect_missing	archive/ignored-without-slash/foo &&
 test_expect_exists	archive/one-level-lower/
 test_expect_missing	archive/one-level-lower/two-levels-lower/ignored-only-if-dir/
 test_expect_missing	archive/one-level-lower/two-levels-lower/ignored-ony-if-dir/ignored-by-ignored-dir
-- 
1.8.2.82.gc24b958