From: Siddharth Shrimali Date: Thu, 08 Oct 2026 06:25:21 GMT Subject: [PATCH] repack: do not rebuild packs on --dry-run Message-ID: <20261008062521.25505-1-r.siddharth.shrimali@gmail.com> "git repack --drop-filtered --dry-run" is documented to list the objects that would be dropped "without rebuilding any pack or deleting anything", but it does both. This is a bug in cmd_repack(): after printing the candidates, the --dry-run block falls through into the regular repack code. repack_promisor_objects() writes a new promisor pack, and with -d, existing_packs_remove_redundant() deletes the old packs. The command still exits successfully, so the user is not told that the repository was modified. The existing guard only skips the implied "delete_redundant = 1", so it does not stop an explicit -d, nor the new pack from being written. Fix it by returning right after the candidates are listed, and add a test that checks the pack directory is unchanged with and without -d. Reported-by: Coy Geek Signed-off-by: Siddharth Shrimali --- Bug report: https://lore.kernel.org/git/CACgTecOm+=vbf50tZNXhcYvRi1ZTsQwbjVoJAbQqs2CmXdJCxg@mail.gmail.com/ builtin/repack.c | 8 ++++++++ t/t7706-repack-drop-filtered.sh | 19 +++++++++++++++++++ 2 files changed, 27 insertions(+) diff --git a/builtin/repack.c b/builtin/repack.c index c4360382c1..c048053912 100644 --- a/builtin/repack.c +++ b/builtin/repack.c @@ -391,6 +391,14 @@ int cmd_repack(int argc, oidset_iter_init(&drop_oids, &iter); while ((oid = oidset_iter_next(&iter))) printf("%s\n", oid_to_hex(oid)); + + /* + * add an exit here, so that dry run does not + * go on to rebuild any pack or delete anything, even + * if the user explicitly asked for -d + */ + ret = 0; + goto cleanup; } } diff --git a/t/t7706-repack-drop-filtered.sh b/t/t7706-repack-drop-filtered.sh index cb36115834..a1c475e4ec 100755 --- a/t/t7706-repack-drop-filtered.sh +++ b/t/t7706-repack-drop-filtered.sh @@ -135,6 +135,25 @@ test_expect_success '--dry-run does not remove the filtered objects' ' git -C repo cat-file -e "$BIG" ' +test_expect_success '--dry-run leaves the pack directory untouched' ' + BIG=$(cat big_oid) && + packdir=repo/.git/objects/pack && + + for opt in "" -d + do + ls $packdir >before && + + git -C repo -c repack.writeBitmaps=false \ + repack --drop-filtered --filter=blob:limit=1k \ + --dry-run -a $opt >out && + + ls $packdir >after && + test_cmp before after && + test_grep "$BIG" out && + git -C repo cat-file -e "$BIG" || return 1 + done +' + test_expect_success '--drop-filtered removes the promisor blob locally' ' BIG=$(cat big_oid) && SMALL=$(cat small_oid) && -- 2.56.0