packed-backend: check whether the "packed-refs" is sorted
When there is a "sorted" trait in the header of the "packed-refs" file, it means that each entry is sorted increasingly by comparing the refname. We should add checks to verify whether the "packed-refs" is sorted in this case. Update the "packed_fsck_ref_header" to know whether there is a "sorted" trail in the header. It may seem that we could record all refnames during the parsing process and then compare later. However, this is not a good design due to the following reasons: 1. Because we need to store the state across the whole checking lifetime, we would consume a lot of memory if there are many entries in the "packed-refs" file. 2. We cannot reuse the existing compare function "cmp_packed_ref_records" which cause repetition. Because "cmp_packed_ref_records" needs an extra parameter "struct snaphost", extract the common part into a new function "cmp_packed_ref_records" to reuse this function to compare. Then, create a new function "packed_fsck_ref_sorted" to parse the file again and user the new fsck message "packedRefUnsorted(ERROR)" to report to the user if the file is not sorted. Mentored-by: Patrick Steinhardt <ps@pks.im> Mentored-by: Karthik Nayak <karthik.188@gmail.com> Signed-off-by: shejialuo <shejialuo@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
shejialuo committed
Feb 28, 2025 at 00:07 UTC
e1c9548eae406a7aa7274685f8bdbc353827bf16
4 files changed
+191
-16
Documentation/fsck-msgids.txt
+3
@@ -187,6 +187,9 @@
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(ERROR) The "packed-refs" file contains an entry that is
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not terminated by a newline.
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+`packedRefUnsorted`::
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+ (ERROR) The "packed-refs" file is not sorted.
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+
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`refMissingNewline`::
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(INFO) A loose ref that does not end with newline(LF). As
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valid implementations of Git never created such a loose ref
fsck.h
+1
@@ -56,6 +56,7 @@ enum fsck_msg_type {
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FUNC(MISSING_TYPE_ENTRY, ERROR) \
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FUNC(MULTIPLE_AUTHORS, ERROR) \
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FUNC(PACKED_REF_ENTRY_NOT_TERMINATED, ERROR) \
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+ FUNC(PACKED_REF_UNSORTED, ERROR) \
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FUNC(TREE_NOT_SORTED, ERROR) \
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FUNC(UNKNOWN_TYPE, ERROR) \
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FUNC(ZERO_PADDED_DATE, ERROR) \
refs/packed-backend.c
+100
-16
@@ -300,14 +300,9 @@ struct snapshot_record {
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size_t len;
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};
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-static int cmp_packed_ref_records(const void *v1, const void *v2,
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- void *cb_data)
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-{
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- const struct snapshot *snapshot = cb_data;
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- const struct snapshot_record *e1 = v1, *e2 = v2;
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- const char *r1 = e1->start + snapshot_hexsz(snapshot) + 1;
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- const char *r2 = e2->start + snapshot_hexsz(snapshot) + 1;
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+static int cmp_packed_refname(const char *r1, const char *r2)
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+{
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while (1) {
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if (*r1 == '\n')
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return *r2 == '\n' ? 0 : -1;
@@ -322,6 +317,17 @@ static int cmp_packed_ref_records(const void *v1, const void *v2,
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}
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}
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+static int cmp_packed_ref_records(const void *v1, const void *v2,
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+ void *cb_data)
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+{
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+ const struct snapshot *snapshot = cb_data;
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+ const struct snapshot_record *e1 = v1, *e2 = v2;
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+ const char *r1 = e1->start + snapshot_hexsz(snapshot) + 1;
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+ const char *r2 = e2->start + snapshot_hexsz(snapshot) + 1;
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+
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+ return cmp_packed_refname(r1, r2);
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+}
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+
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/*
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* Compare a snapshot record at `rec` to the specified NUL-terminated
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* refname.
@@ -1797,19 +1803,33 @@ static int packed_fsck_ref_next_line(struct fsck_options *o,
1803
}
1804
1805
static int packed_fsck_ref_header(struct fsck_options *o,
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- const char *start, const char *eol)
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+ const char *start, const char *eol,
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+ unsigned int *sorted)
1808
{
1802
- if (!starts_with(start, "# pack-refs with: ")) {
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+ struct string_list traits = STRING_LIST_INIT_NODUP;
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+ char *tmp_line;
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+ int ret = 0;
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+ char *p;
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+
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+ tmp_line = xmemdupz(start, eol - start);
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+ if (!skip_prefix(tmp_line, "# pack-refs with: ", (const char **)&p)) {
1816
struct fsck_ref_report report = { 0 };
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report.path = "packed-refs.header";
1818
1806
- return fsck_report_ref(o, &report,
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- FSCK_MSG_BAD_PACKED_REF_HEADER,
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- "'%.*s' does not start with '# pack-refs with: '",
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- (int)(eol - start), start);
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+ ret = fsck_report_ref(o, &report,
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+ FSCK_MSG_BAD_PACKED_REF_HEADER,
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+ "'%.*s' does not start with '# pack-refs with: '",
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+ (int)(eol - start), start);
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+ goto cleanup;
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}
1825
1812
- return 0;
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+ string_list_split_in_place(&traits, p, " ", -1);
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+ *sorted = unsorted_string_list_has_string(&traits, "sorted");
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+
1829
+cleanup:
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+ free(tmp_line);
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+ string_list_clear(&traits, 0);
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+ return ret;
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}
1834
1835
static int packed_fsck_ref_peeled_line(struct fsck_options *o,
@@ -1915,8 +1935,68 @@ cleanup:
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return ret;
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}
1937
1938
+static int packed_fsck_ref_sorted(struct fsck_options *o,
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+ struct ref_store *ref_store,
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+ const char *start, const char *eof)
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+{
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+ size_t hexsz = ref_store->repo->hash_algo->hexsz;
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+ struct strbuf packed_entry = STRBUF_INIT;
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+ struct fsck_ref_report report = { 0 };
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+ struct strbuf refname1 = STRBUF_INIT;
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+ struct strbuf refname2 = STRBUF_INIT;
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+ unsigned long line_number = 1;
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+ const char *former = NULL;
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+ const char *current;
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+ const char *eol;
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+ int ret = 0;
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+
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+ if (*start == '#') {
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+ eol = memchr(start, '\n', eof - start);
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+ start = eol + 1;
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+ line_number++;
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+ }
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+
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+ for (; start < eof; line_number++, start = eol + 1) {
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+ eol = memchr(start, '\n', eof - start);
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+
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+ if (*start == '^')
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+ continue;
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+
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+ if (!former) {
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+ former = start + hexsz + 1;
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+ continue;
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+ }
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+
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+ current = start + hexsz + 1;
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+ if (cmp_packed_refname(former, current) >= 0) {
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+ const char *err_fmt =
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+ "refname '%s' is less than previous refname '%s'";
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+
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+ eol = memchr(former, '\n', eof - former);
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+ strbuf_add(&refname1, former, eol - former);
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+ eol = memchr(current, '\n', eof - current);
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+ strbuf_add(&refname2, current, eol - current);
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+
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+ strbuf_addf(&packed_entry, "packed-refs line %lu", line_number);
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+ report.path = packed_entry.buf;
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+ ret = fsck_report_ref(o, &report,
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+ FSCK_MSG_PACKED_REF_UNSORTED,
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+ err_fmt, refname2.buf, refname1.buf);
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+ goto cleanup;
1986
+ }
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+ former = current;
1988
+ }
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+
1990
+cleanup:
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+ strbuf_release(&packed_entry);
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+ strbuf_release(&refname1);
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+ strbuf_release(&refname2);
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+ return ret;
1995
+}
1996
+
1997
static int packed_fsck_ref_content(struct fsck_options *o,
1998
struct ref_store *ref_store,
1999
+ unsigned int *sorted,
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const char *start, const char *eof)
2001
{
2002
struct strbuf refname = STRBUF_INIT;
@@ -1926,7 +2006,7 @@ static int packed_fsck_ref_content(struct fsck_options *o,
2006
2007
ret |= packed_fsck_ref_next_line(o, line_number, start, eof, &eol);
2008
if (*start == '#') {
1929
- ret |= packed_fsck_ref_header(o, start, eol);
2009
+ ret |= packed_fsck_ref_header(o, start, eol, sorted);
2010
2011
start = eol + 1;
2012
line_number++;
@@ -1957,6 +2037,7 @@ static int packed_fsck(struct ref_store *ref_store,
2037
struct packed_ref_store *refs = packed_downcast(ref_store,
2038
REF_STORE_READ, "fsck");
2039
struct strbuf packed_ref_content = STRBUF_INIT;
2040
+ unsigned int sorted = 0;
2041
struct stat st;
2042
int ret = 0;
2043
int fd = -1;
@@ -2004,8 +2085,11 @@ static int packed_fsck(struct ref_store *ref_store,
2085
goto cleanup;
2086
}
2087
2007
- ret = packed_fsck_ref_content(o, ref_store, packed_ref_content.buf,
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+ ret = packed_fsck_ref_content(o, ref_store, &sorted, packed_ref_content.buf,
2089
packed_ref_content.buf + packed_ref_content.len);
2090
+ if (!ret && sorted)
2091
+ ret = packed_fsck_ref_sorted(o, ref_store, packed_ref_content.buf,
2092
+ packed_ref_content.buf + packed_ref_content.len);
2093
2094
cleanup:
2095
if (fd >= 0)
t/t0602-reffiles-fsck.sh
+87
@@ -743,4 +743,91 @@ test_expect_success 'packed-refs content should be checked' '
743
)
744
'
745
746
+test_expect_success 'packed-ref with sorted trait should be checked' '
747
+ test_when_finished "rm -rf repo" &&
748
+ git init repo &&
749
+ (
750
+ cd repo &&
751
+ test_commit default &&
752
+ git branch branch-1 &&
753
+ git branch branch-2 &&
754
+ git tag -a annotated-tag-1 -m tag-1 &&
755
+ branch_1_oid=$(git rev-parse branch-1) &&
756
+ branch_2_oid=$(git rev-parse branch-2) &&
757
+ tag_1_oid=$(git rev-parse annotated-tag-1) &&
758
+ tag_1_peeled_oid=$(git rev-parse annotated-tag-1^{}) &&
759
+ refname1="refs/heads/main" &&
760
+ refname2="refs/heads/foo" &&
761
+ refname3="refs/tags/foo" &&
762
+
763
+ cat >.git/packed-refs <<-EOF &&
764
+ # pack-refs with: peeled fully-peeled sorted
765
+ EOF
766
+ git refs verify 2>err &&
767
+ rm .git/packed-refs &&
768
+ test_must_be_empty err &&
769
+
770
+ cat >.git/packed-refs <<-EOF &&
771
+ # pack-refs with: peeled fully-peeled sorted
772
+ $branch_2_oid $refname1
773
+ EOF
774
+ git refs verify 2>err &&
775
+ rm .git/packed-refs &&
776
+ test_must_be_empty err &&
777
+
778
+ cat >.git/packed-refs <<-EOF &&
779
+ # pack-refs with: peeled fully-peeled sorted
780
+ $branch_2_oid $refname1
781
+ $branch_1_oid $refname2
782
+ $tag_1_oid $refname3
783
+ EOF
784
+ test_must_fail git refs verify 2>err &&
785
+ cat >expect <<-EOF &&
786
+ error: packed-refs line 3: packedRefUnsorted: refname '\''$refname2'\'' is less than previous refname '\''$refname1'\''
787
+ EOF
788
+ rm .git/packed-refs &&
789
+ test_cmp expect err &&
790
+
791
+ cat >.git/packed-refs <<-EOF &&
792
+ # pack-refs with: peeled fully-peeled sorted
793
+ $tag_1_oid $refname3
794
+ ^$tag_1_peeled_oid
795
+ $branch_2_oid $refname2
796
+ EOF
797
+ test_must_fail git refs verify 2>err &&
798
+ cat >expect <<-EOF &&
799
+ error: packed-refs line 4: packedRefUnsorted: refname '\''$refname2'\'' is less than previous refname '\''$refname3'\''
800
+ EOF
801
+ rm .git/packed-refs &&
802
+ test_cmp expect err
803
+ )
804
+'
805
+
806
+test_expect_success 'packed-ref without sorted trait should not be checked' '
807
+ test_when_finished "rm -rf repo" &&
808
+ git init repo &&
809
+ (
810
+ cd repo &&
811
+ test_commit default &&
812
+ git branch branch-1 &&
813
+ git branch branch-2 &&
814
+ git tag -a annotated-tag-1 -m tag-1 &&
815
+ branch_1_oid=$(git rev-parse branch-1) &&
816
+ branch_2_oid=$(git rev-parse branch-2) &&
817
+ tag_1_oid=$(git rev-parse annotated-tag-1) &&
818
+ tag_1_peeled_oid=$(git rev-parse annotated-tag-1^{}) &&
819
+ refname1="refs/heads/main" &&
820
+ refname2="refs/heads/foo" &&
821
+ refname3="refs/tags/foo" &&
822
+
823
+ cat >.git/packed-refs <<-EOF &&
824
+ # pack-refs with: peeled fully-peeled
825
+ $branch_2_oid $refname1
826
+ $branch_1_oid $refname2
827
+ EOF
828
+ git refs verify 2>err &&
829
+ test_must_be_empty err
830
+ )
831
+'
832
+
833
test_done