diff mbox series

[12/15] refs/packed-backend.c: ignore complicated hidden refs rules

Message ID dd5b34185cdb42eb43738aa837e811e42739b659.1683581621.git.me@ttaylorr.com (mailing list archive)
State New, archived
Headers show
Series refs: implement skip lists for packed backend | expand

Commit Message

Taylor Blau May 8, 2023, 10 p.m. UTC
In subsequent commits, we'll teach `receive-pack` and `upload-pack` to
use the new skip-list feature in the packed-refs iterator by ignoring
references which are mentioned via its respective hideRefs lists.

However, the packed-ref skip lists cannot handle un-hiding rules (that
begin with '!'), or namespace comparisons (that begin with '^'). Detect
and avoid these cases by falling back to the normal enumeration without
a skip list when such patterns exist.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
---
 refs/packed-backend.c   | 19 +++++++++++++++++++
 t/t1419-exclude-refs.sh | 10 ++++++++++
 2 files changed, 29 insertions(+)
diff mbox series

Patch

diff --git a/refs/packed-backend.c b/refs/packed-backend.c
index ddfa9add14..7f09201f35 100644
--- a/refs/packed-backend.c
+++ b/refs/packed-backend.c
@@ -1013,6 +1013,25 @@  static void populate_excluded_skip_list(struct packed_ref_iterator *iter,
 	if (!excluded_patterns)
 		return;
 
+	for (pattern = excluded_patterns; *pattern; pattern++) {
+		/*
+		 * We also can't feed any excludes from hidden refs
+		 * config sections, since later rules may override
+		 * previous ones. For example, with rules "refs/foo" and
+		 * "!refs/foo/bar", we should show "refs/foo/bar" (and
+		 * everything underneath it), but the earlier exclusion
+		 * would cause us to skip all of "refs/foo". We likewise
+		 * don't implement the namespace stripping required for
+		 * '^' rules.
+		 *
+		 * Both are possible to do, but complicated, so avoid
+		 * populating the skip list at all if we see either of
+		 * these patterns.
+		 */
+		if (**pattern == '!' || **pattern == '^')
+			return;
+	}
+
 	for (pattern = excluded_patterns; *pattern; pattern++) {
 		struct skip_list_entry *e;
 
diff --git a/t/t1419-exclude-refs.sh b/t/t1419-exclude-refs.sh
index 051b5a54ce..026e4414cd 100755
--- a/t/t1419-exclude-refs.sh
+++ b/t/t1419-exclude-refs.sh
@@ -118,4 +118,14 @@  test_expect_success 'for_each_ref__exclude(refs/heads/ba*)' '
 	assert_no_skips
 '
 
+test_expect_success 'for_each_ref__exclude(refs/heads/foo, !refs/heads/foo/1)' '
+	# discards complex hidden ref rules
+	for_each_ref__exclude refs/heads refs/heads/foo "!refs/heads/foo/1" \
+		>actual 2>perf &&
+	for_each_ref >expect &&
+
+	test_cmp expect actual &&
+	assert_no_skips
+'
+
 test_done