27 files changed, 804 insertions, 311 deletions

diff --git a/t/README b/t/README
index 29576c3748..bdfac4cceb 100644
--- a/t/README
+++ b/t/README
@@ -475,7 +475,7 @@ GIT_TEST_DEFAULT_HASH=<hash-algo> specifies which hash algorithm to
 use in the test scripts. Recognized values for <hash-algo> are "sha1"
 and "sha256".
 
-GIT_TEST_WRITE_REV_INDEX=<boolean>, when true enables the
+GIT_TEST_NO_WRITE_REV_INDEX=<boolean>, when true disables the
 'pack.writeReverseIndex' setting.
 
 GIT_TEST_SPARSE_INDEX=<boolean>, when true enables index writes to use the
diff --git a/t/helper/test-chmtime.c b/t/helper/test-chmtime.c
index dc28890a18..0e5538833a 100644
--- a/t/helper/test-chmtime.c
+++ b/t/helper/test-chmtime.c
@@ -94,7 +94,7 @@ int cmd__chmtime(int argc, const char **argv)
 	if (timespec_arg(argv[i], &set_time, &set_eq)) {
 		++i;
 	} else {
-		if (get == 0) {
+		if (get == 0 && verbose == 0) {
 			fprintf(stderr, "Not a base-10 integer: %s\n", argv[i] + 1);
 			goto usage;
 		}
diff --git a/t/helper/test-date.c b/t/helper/test-date.c
index 2d9232cc68..0683d46574 100644
--- a/t/helper/test-date.c
+++ b/t/helper/test-date.c
@@ -1,6 +1,6 @@
 #include "test-tool.h"
-#include "cache.h"
 #include "date.h"
+#include "trace.h"
 
 static const char *usage_msg = "\n"
 "  test-tool date relative [time_t]...\n"
diff --git a/t/helper/test-fast-rebase.c b/t/helper/test-fast-rebase.c
index fd48e0ee2c..d1d63feaa9 100644
--- a/t/helper/test-fast-rebase.c
+++ b/t/helper/test-fast-rebase.c
@@ -20,6 +20,7 @@
 #include "hex.h"
 #include "lockfile.h"
 #include "merge-ort.h"
+#include "object-name.h"
 #include "refs.h"
 #include "revision.h"
 #include "sequencer.h"
diff --git a/t/helper/test-lazy-init-name-hash.c b/t/helper/test-lazy-init-name-hash.c
index 06ce3a47cc..f23d983c11 100644
--- a/t/helper/test-lazy-init-name-hash.c
+++ b/t/helper/test-lazy-init-name-hash.c
@@ -4,6 +4,7 @@
 #include "environment.h"
 #include "parse-options.h"
 #include "setup.h"
+#include "trace.h"
 
 static int single;
 static int multi;
diff --git a/t/helper/test-match-trees.c b/t/helper/test-match-trees.c
index 508eb7066a..35a2b8005c 100644
--- a/t/helper/test-match-trees.c
+++ b/t/helper/test-match-trees.c
@@ -1,6 +1,7 @@
 #include "test-tool.h"
 #include "cache.h"
 #include "hex.h"
+#include "object-name.h"
 #include "setup.h"
 #include "tree.h"
 
diff --git a/t/helper/test-mergesort.c b/t/helper/test-mergesort.c
index 335e5bb3a9..737e0c5235 100644
--- a/t/helper/test-mergesort.c
+++ b/t/helper/test-mergesort.c
@@ -1,5 +1,6 @@
 #include "test-tool.h"
 #include "cache.h"
+#include "mem-pool.h"
 #include "mergesort.h"
 
 static uint32_t minstd_rand(uint32_t *state)
diff --git a/t/helper/test-oidmap.c b/t/helper/test-oidmap.c
index a7b7b38df1..1b0e7eecb4 100644
--- a/t/helper/test-oidmap.c
+++ b/t/helper/test-oidmap.c
@@ -1,6 +1,6 @@
 #include "test-tool.h"
-#include "cache.h"
 #include "hex.h"
+#include "object-name.h"
 #include "oidmap.h"
 #include "setup.h"
 #include "strbuf.h"
diff --git a/t/helper/test-path-utils.c b/t/helper/test-path-utils.c
index 4f5ac2fadc..6355c9e4b6 100644
--- a/t/helper/test-path-utils.c
+++ b/t/helper/test-path-utils.c
@@ -4,6 +4,7 @@
 #include "environment.h"
 #include "setup.h"
 #include "string-list.h"
+#include "trace.h"
 #include "utf8.h"
 
 /*
diff --git a/t/helper/test-reach.c b/t/helper/test-reach.c
index b0deaa106a..5b6f217441 100644
--- a/t/helper/test-reach.c
+++ b/t/helper/test-reach.c
@@ -1,11 +1,11 @@
 #include "test-tool.h"
-#include "cache.h"
 #include "alloc.h"
 #include "commit.h"
 #include "commit-reach.h"
 #include "config.h"
 #include "gettext.h"
 #include "hex.h"
+#include "object-name.h"
 #include "parse-options.h"
 #include "ref-filter.h"
 #include "setup.h"
diff --git a/t/helper/test-submodule-config.c b/t/helper/test-submodule-config.c
index 40a6ee45af..5e462faa9d 100644
--- a/t/helper/test-submodule-config.c
+++ b/t/helper/test-submodule-config.c
@@ -1,6 +1,6 @@
 #include "test-tool.h"
-#include "cache.h"
 #include "config.h"
+#include "object-name.h"
 #include "setup.h"
 #include "submodule-config.h"
 #include "submodule.h"
diff --git a/t/perf/p5312-pack-bitmaps-revs.sh b/t/perf/p5312-pack-bitmaps-revs.sh
index 0684b690af..ceec60656b 100755
--- a/t/perf/p5312-pack-bitmaps-revs.sh
+++ b/t/perf/p5312-pack-bitmaps-revs.sh
@@ -12,8 +12,7 @@ test_lookup_pack_bitmap () {
 	test_perf_large_repo
 
 	test_expect_success 'setup bitmap config' '
-		git config pack.writebitmaps true &&
-		git config pack.writeReverseIndex true
+		git config pack.writebitmaps true
 	'
 
 	# we need to create the tag up front such that it is covered by the repack and
diff --git a/t/t1300-config.sh b/t/t1300-config.sh
index 2575279ab8..f1d42b62b0 100755
--- a/t/t1300-config.sh
+++ b/t/t1300-config.sh
@@ -617,6 +617,36 @@ test_expect_success 'renaming to bogus section is rejected' '
 	test_must_fail git config --rename-section branch.zwei "bogus name"
 '
 
+test_expect_success 'renaming a section with a long line' '
+	{
+		printf "[b]\\n" &&
+		printf "  c = d %1024s [a] e = f\\n" " " &&
+		printf "[a] g = h\\n"
+	} >y &&
+	git config -f y --rename-section a xyz &&
+	test_must_fail git config -f y b.e
+'
+
+test_expect_success 'renaming an embedded section with a long line' '
+	{
+		printf "[b]\\n" &&
+		printf "  c = d %1024s [a] [foo] e = f\\n" " " &&
+		printf "[a] g = h\\n"
+	} >y &&
+	git config -f y --rename-section a xyz &&
+	test_must_fail git config -f y foo.e
+'
+
+test_expect_success 'renaming a section with an overly-long line' '
+	{
+		printf "[b]\\n" &&
+		printf "  c = d %525000s e" " " &&
+		printf "[a] g = h\\n"
+	} >y &&
+	test_must_fail git config -f y --rename-section a xyz 2>err &&
+	grep "refusing to work with overly long line in .y. on line 2" err
+'
+
 cat >> .git/config << EOF
   [branch "zwei"] a = 1 [branch "vier"]
 EOF
diff --git a/t/t4115-apply-symlink.sh b/t/t4115-apply-symlink.sh
index 65ac7df2d7..e95e6d4e7d 100755
--- a/t/t4115-apply-symlink.sh
+++ b/t/t4115-apply-symlink.sh
@@ -126,4 +126,19 @@ test_expect_success SYMLINKS 'symlink escape when deleting file' '
 	test_path_is_file .git/delete-me
 '
 
+test_expect_success SYMLINKS '--reject removes .rej symlink if it exists' '
+	test_when_finished "git reset --hard && git clean -dfx" &&
+
+	test_commit file &&
+	echo modified >file.t &&
+	git diff -- file.t >patch &&
+	echo modified-again >file.t &&
+
+	ln -s foo file.t.rej &&
+	test_must_fail git apply patch --reject 2>err &&
+	test_i18ngrep "Rejected hunk" err &&
+	test_path_is_missing foo &&
+	test_path_is_file file.t.rej
+'
+
 test_done
diff --git a/t/t5300-pack-object.sh b/t/t5300-pack-object.sh
index f8a0f309e2..d2ce236d61 100755
--- a/t/t5300-pack-object.sh
+++ b/t/t5300-pack-object.sh
@@ -589,141 +589,6 @@ test_expect_success 'prefetch objects' '
 	test_line_count = 1 donelines
 '
 
-test_expect_success 'setup for --stdin-packs tests' '
-	git init stdin-packs &&
-	(
-		cd stdin-packs &&
-
-		test_commit A &&
-		test_commit B &&
-		test_commit C &&
-
-		for id in A B C
-		do
-			git pack-objects .git/objects/pack/pack-$id \
-				--incremental --revs <<-EOF || exit 1
-			refs/tags/$id
-			EOF
-		done &&
-
-		ls -la .git/objects/pack
-	)
-'
-
-test_expect_success '--stdin-packs with excluded packs' '
-	(
-		cd stdin-packs &&
-
-		PACK_A="$(basename .git/objects/pack/pack-A-*.pack)" &&
-		PACK_B="$(basename .git/objects/pack/pack-B-*.pack)" &&
-		PACK_C="$(basename .git/objects/pack/pack-C-*.pack)" &&
-
-		git pack-objects test --stdin-packs <<-EOF &&
-		$PACK_A
-		^$PACK_B
-		$PACK_C
-		EOF
-
-		(
-			git show-index <$(ls .git/objects/pack/pack-A-*.idx) &&
-			git show-index <$(ls .git/objects/pack/pack-C-*.idx)
-		) >expect.raw &&
-		git show-index <$(ls test-*.idx) >actual.raw &&
-
-		cut -d" " -f2 <expect.raw | sort >expect &&
-		cut -d" " -f2 <actual.raw | sort >actual &&
-		test_cmp expect actual
-	)
-'
-
-test_expect_success '--stdin-packs is incompatible with --filter' '
-	(
-		cd stdin-packs &&
-		test_must_fail git pack-objects --stdin-packs --stdout \
-			--filter=blob:none </dev/null 2>err &&
-		test_i18ngrep "cannot use --filter with --stdin-packs" err
-	)
-'
-
-test_expect_success '--stdin-packs is incompatible with --revs' '
-	(
-		cd stdin-packs &&
-		test_must_fail git pack-objects --stdin-packs --revs out \
-			</dev/null 2>err &&
-		test_i18ngrep "cannot use internal rev list with --stdin-packs" err
-	)
-'
-
-test_expect_success '--stdin-packs with loose objects' '
-	(
-		cd stdin-packs &&
-
-		PACK_A="$(basename .git/objects/pack/pack-A-*.pack)" &&
-		PACK_B="$(basename .git/objects/pack/pack-B-*.pack)" &&
-		PACK_C="$(basename .git/objects/pack/pack-C-*.pack)" &&
-
-		test_commit D && # loose
-
-		git pack-objects test2 --stdin-packs --unpacked <<-EOF &&
-		$PACK_A
-		^$PACK_B
-		$PACK_C
-		EOF
-
-		(
-			git show-index <$(ls .git/objects/pack/pack-A-*.idx) &&
-			git show-index <$(ls .git/objects/pack/pack-C-*.idx) &&
-			git rev-list --objects --no-object-names \
-				refs/tags/C..refs/tags/D
-
-		) >expect.raw &&
-		ls -la . &&
-		git show-index <$(ls test2-*.idx) >actual.raw &&
-
-		cut -d" " -f2 <expect.raw | sort >expect &&
-		cut -d" " -f2 <actual.raw | sort >actual &&
-		test_cmp expect actual
-	)
-'
-
-test_expect_success '--stdin-packs with broken links' '
-	(
-		cd stdin-packs &&
-
-		# make an unreachable object with a bogus parent
-		git cat-file -p HEAD >commit &&
-		sed "s/$(git rev-parse HEAD^)/$(test_oid zero)/" <commit |
-		git hash-object -w -t commit --stdin >in &&
-
-		git pack-objects .git/objects/pack/pack-D <in &&
-
-		PACK_A="$(basename .git/objects/pack/pack-A-*.pack)" &&
-		PACK_B="$(basename .git/objects/pack/pack-B-*.pack)" &&
-		PACK_C="$(basename .git/objects/pack/pack-C-*.pack)" &&
-		PACK_D="$(basename .git/objects/pack/pack-D-*.pack)" &&
-
-		git pack-objects test3 --stdin-packs --unpacked <<-EOF &&
-		$PACK_A
-		^$PACK_B
-		$PACK_C
-		$PACK_D
-		EOF
-
-		(
-			git show-index <$(ls .git/objects/pack/pack-A-*.idx) &&
-			git show-index <$(ls .git/objects/pack/pack-C-*.idx) &&
-			git show-index <$(ls .git/objects/pack/pack-D-*.idx) &&
-			git rev-list --objects --no-object-names \
-				refs/tags/C..refs/tags/D
-		) >expect.raw &&
-		git show-index <$(ls test3-*.idx) >actual.raw &&
-
-		cut -d" " -f2 <expect.raw | sort >expect &&
-		cut -d" " -f2 <actual.raw | sort >actual &&
-		test_cmp expect actual
-	)
-'
-
 test_expect_success 'negative window clamps to 0' '
 	git pack-objects --progress --window=-1 neg-window <obj-list 2>stderr &&
 	check_deltas stderr = 0
diff --git a/t/t5304-prune.sh b/t/t5304-prune.sh
index 5500dd0842..662ae9b152 100755
--- a/t/t5304-prune.sh
+++ b/t/t5304-prune.sh
@@ -62,11 +62,11 @@ test_expect_success 'prune --expire' '
 test_expect_success 'gc: implicit prune --expire' '
 	add_blob &&
 	test-tool chmtime =-$((2*$week-30)) $BLOB_FILE &&
-	git gc &&
+	git gc --no-cruft &&
 	verbose test $((1 + $before)) = $(git count-objects | sed "s/ .*//") &&
 	test_path_is_file $BLOB_FILE &&
 	test-tool chmtime =-$((2*$week+1)) $BLOB_FILE &&
-	git gc &&
+	git gc --no-cruft &&
 	verbose test $before = $(git count-objects | sed "s/ .*//") &&
 	test_path_is_missing $BLOB_FILE
 '
@@ -86,7 +86,7 @@ test_expect_success 'gc: refuse to start with invalid gc.pruneExpire' '
 
 test_expect_success 'gc: start with ok gc.pruneExpire' '
 	git config gc.pruneExpire 2.days.ago &&
-	git gc
+	git gc --no-cruft
 '
 
 test_expect_success 'prune: prune nonsense parameters' '
@@ -137,44 +137,44 @@ test_expect_success 'gc --no-prune' '
 	add_blob &&
 	test-tool chmtime =-$((5001*$day)) $BLOB_FILE &&
 	git config gc.pruneExpire 2.days.ago &&
-	git gc --no-prune &&
+	git gc --no-prune --no-cruft &&
 	verbose test 1 = $(git count-objects | sed "s/ .*//") &&
 	test_path_is_file $BLOB_FILE
 '
 
 test_expect_success 'gc respects gc.pruneExpire' '
 	git config gc.pruneExpire 5002.days.ago &&
-	git gc &&
+	git gc --no-cruft &&
 	test_path_is_file $BLOB_FILE &&
 	git config gc.pruneExpire 5000.days.ago &&
-	git gc &&
+	git gc --no-cruft &&
 	test_path_is_missing $BLOB_FILE
 '
 
 test_expect_success 'gc --prune=<date>' '
 	add_blob &&
 	test-tool chmtime =-$((5001*$day)) $BLOB_FILE &&
-	git gc --prune=5002.days.ago &&
+	git gc --prune=5002.days.ago --no-cruft &&
 	test_path_is_file $BLOB_FILE &&
-	git gc --prune=5000.days.ago &&
+	git gc --prune=5000.days.ago --no-cruft &&
 	test_path_is_missing $BLOB_FILE
 '
 
 test_expect_success 'gc --prune=never' '
 	add_blob &&
-	git gc --prune=never &&
+	git gc --prune=never --no-cruft &&
 	test_path_is_file $BLOB_FILE &&
-	git gc --prune=now &&
+	git gc --prune=now --no-cruft &&
 	test_path_is_missing $BLOB_FILE
 '
 
 test_expect_success 'gc respects gc.pruneExpire=never' '
 	git config gc.pruneExpire never &&
 	add_blob &&
-	git gc &&
+	git gc --no-cruft &&
 	test_path_is_file $BLOB_FILE &&
 	git config gc.pruneExpire now &&
-	git gc &&
+	git gc --no-cruft &&
 	test_path_is_missing $BLOB_FILE
 '
 
@@ -194,7 +194,7 @@ test_expect_success 'gc: prune old objects after local clone' '
 		cd aclone &&
 		verbose test 1 = $(git count-objects | sed "s/ .*//") &&
 		test_path_is_file $BLOB_FILE &&
-		git gc --prune &&
+		git gc --prune --no-cruft &&
 		verbose test 0 = $(git count-objects | sed "s/ .*//") &&
 		test_path_is_missing $BLOB_FILE
 	)
@@ -237,7 +237,7 @@ test_expect_success 'clean pack garbage with gc' '
 	>.git/objects/pack/fake2.keep &&
 	>.git/objects/pack/fake2.idx &&
 	>.git/objects/pack/fake3.keep &&
-	git gc &&
+	git gc --no-cruft &&
 	git count-objects -v 2>stderr &&
 	grep "^warning:" stderr | sort >actual &&
 	cat >expected <<\EOF &&
diff --git a/t/t5319-multi-pack-index.sh b/t/t5319-multi-pack-index.sh
index 499d5d4c78..0883c7c6bd 100755
--- a/t/t5319-multi-pack-index.sh
+++ b/t/t5319-multi-pack-index.sh
@@ -183,6 +183,18 @@ test_expect_success 'write midx with --stdin-packs' '
 
 compare_results_with_midx "mixed mode (one pack + extra)"
 
+test_expect_success 'write with no objects and preferred pack' '
+	test_when_finished "rm -rf empty" &&
+	git init empty &&
+	test_must_fail git -C empty multi-pack-index write \
+		--stdin-packs --preferred-pack=does-not-exist </dev/null 2>err &&
+	cat >expect <<-EOF &&
+	warning: unknown preferred pack: ${SQ}does-not-exist${SQ}
+	error: no pack files to index.
+	EOF
+	test_cmp expect err
+'
+
 test_expect_success 'write progress off for redirected stderr' '
 	git multi-pack-index --object-dir=$objdir write 2>err &&
 	test_line_count = 0 err
diff --git a/t/t5325-reverse-index.sh b/t/t5325-reverse-index.sh
index d042d26f2b..431a603ca0 100755
--- a/t/t5325-reverse-index.sh
+++ b/t/t5325-reverse-index.sh
@@ -1,17 +1,20 @@
 #!/bin/sh
 
 test_description='on-disk reverse index'
+
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 # The below tests want control over the 'pack.writeReverseIndex' setting
 # themselves to assert various combinations of it with other options.
-sane_unset GIT_TEST_WRITE_REV_INDEX
+sane_unset GIT_TEST_NO_WRITE_REV_INDEX
 
 packdir=.git/objects/pack
 
 test_expect_success 'setup' '
 	test_commit base &&
 
+	test_config pack.writeReverseIndex false &&
 	pack=$(git pack-objects --all $packdir/pack) &&
 	rev=$packdir/pack-$pack.rev &&
 
@@ -94,6 +97,17 @@ test_expect_success 'reverse index is not generated when available on disk' '
 		--batch-check="%(objectsize:disk)" <tip
 '
 
+test_expect_success 'reverse index is ignored when pack.readReverseIndex is false' '
+	test_index_pack true &&
+	test_path_is_file $rev &&
+
+	test_config pack.readReverseIndex false &&
+
+	git rev-parse HEAD >tip &&
+	GIT_TEST_REV_INDEX_DIE_ON_DISK=1 git cat-file \
+		--batch-check="%(objectsize:disk)" <tip
+'
+
 test_expect_success 'revindex in-memory vs on-disk' '
 	git init repo &&
 	test_when_finished "rm -fr repo" &&
@@ -117,4 +131,78 @@ test_expect_success 'revindex in-memory vs on-disk' '
 		test_cmp on-disk in-core
 	)
 '
+
+test_expect_success 'fsck succeeds on good rev-index' '
+	test_when_finished rm -fr repo &&
+	git init repo &&
+	(
+		cd repo &&
+
+		test_commit commit &&
+		git -c pack.writeReverseIndex=true repack -ad &&
+		git fsck 2>err &&
+		test_must_be_empty err
+	)
+'
+
+test_expect_success 'set up rev-index corruption tests' '
+	git init corrupt &&
+	(
+		cd corrupt &&
+
+		test_commit commit &&
+		git -c pack.writeReverseIndex=true repack -ad &&
+
+		revfile=$(ls .git/objects/pack/pack-*.rev) &&
+		chmod a+w $revfile &&
+		cp $revfile $revfile.bak
+	)
+'
+
+corrupt_rev_and_verify () {
+	(
+		pos="$1" &&
+		value="$2" &&
+		error="$3" &&
+
+		cd corrupt &&
+		revfile=$(ls .git/objects/pack/pack-*.rev) &&
+
+		# Reset to original rev-file.
+		cp $revfile.bak $revfile &&
+
+		printf "$value" | dd of=$revfile bs=1 seek="$pos" conv=notrunc &&
+		test_must_fail git fsck 2>err &&
+		grep "$error" err
+	)
+}
+
+test_expect_success 'fsck catches invalid checksum' '
+	revfile=$(ls corrupt/.git/objects/pack/pack-*.rev) &&
+	orig_size=$(wc -c <$revfile) &&
+	hashpos=$((orig_size - 10)) &&
+	corrupt_rev_and_verify $hashpos bogus \
+		"invalid checksum"
+'
+
+test_expect_success 'fsck catches invalid row position' '
+	corrupt_rev_and_verify 14 "\07" \
+		"invalid rev-index position"
+'
+
+test_expect_success 'fsck catches invalid header: magic number' '
+	corrupt_rev_and_verify 1 "\07" \
+		"reverse-index file .* has unknown signature"
+'
+
+test_expect_success 'fsck catches invalid header: version' '
+	corrupt_rev_and_verify 7 "\02" \
+		"reverse-index file .* has unsupported version"
+'
+
+test_expect_success 'fsck catches invalid header: hash function' '
+	corrupt_rev_and_verify 11 "\03" \
+		"reverse-index file .* has unsupported hash id"
+'
+
 test_done
diff --git a/t/t5331-pack-objects-stdin.sh b/t/t5331-pack-objects-stdin.sh
new file mode 100755
index 0000000000..acab31667a
--- /dev/null
+++ b/t/t5331-pack-objects-stdin.sh
@@ -0,0 +1,240 @@
+#!/bin/sh
+
+test_description='pack-objects --stdin'
+GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
+export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
+
+TEST_PASSES_SANITIZE_LEAK=true
+. ./test-lib.sh
+
+packed_objects () {
+	git show-index <"$1" >tmp-object-list &&
+	cut -d' ' -f2 tmp-object-list | sort &&
+	rm tmp-object-list
+ }
+
+test_expect_success 'setup for --stdin-packs tests' '
+	git init stdin-packs &&
+	(
+		cd stdin-packs &&
+
+		test_commit A &&
+		test_commit B &&
+		test_commit C &&
+
+		for id in A B C
+		do
+			git pack-objects .git/objects/pack/pack-$id \
+				--incremental --revs <<-EOF || exit 1
+			refs/tags/$id
+			EOF
+		done &&
+
+		ls -la .git/objects/pack
+	)
+'
+
+test_expect_success '--stdin-packs with excluded packs' '
+	(
+		cd stdin-packs &&
+
+		PACK_A="$(basename .git/objects/pack/pack-A-*.pack)" &&
+		PACK_B="$(basename .git/objects/pack/pack-B-*.pack)" &&
+		PACK_C="$(basename .git/objects/pack/pack-C-*.pack)" &&
+
+		git pack-objects test --stdin-packs <<-EOF &&
+		$PACK_A
+		^$PACK_B
+		$PACK_C
+		EOF
+
+		(
+			git show-index <$(ls .git/objects/pack/pack-A-*.idx) &&
+			git show-index <$(ls .git/objects/pack/pack-C-*.idx)
+		) >expect.raw &&
+		git show-index <$(ls test-*.idx) >actual.raw &&
+
+		cut -d" " -f2 <expect.raw | sort >expect &&
+		cut -d" " -f2 <actual.raw | sort >actual &&
+		test_cmp expect actual
+	)
+'
+
+test_expect_success '--stdin-packs is incompatible with --filter' '
+	(
+		cd stdin-packs &&
+		test_must_fail git pack-objects --stdin-packs --stdout \
+			--filter=blob:none </dev/null 2>err &&
+		test_i18ngrep "cannot use --filter with --stdin-packs" err
+	)
+'
+
+test_expect_success '--stdin-packs is incompatible with --revs' '
+	(
+		cd stdin-packs &&
+		test_must_fail git pack-objects --stdin-packs --revs out \
+			</dev/null 2>err &&
+		test_i18ngrep "cannot use internal rev list with --stdin-packs" err
+	)
+'
+
+test_expect_success '--stdin-packs with loose objects' '
+	(
+		cd stdin-packs &&
+
+		PACK_A="$(basename .git/objects/pack/pack-A-*.pack)" &&
+		PACK_B="$(basename .git/objects/pack/pack-B-*.pack)" &&
+		PACK_C="$(basename .git/objects/pack/pack-C-*.pack)" &&
+
+		test_commit D && # loose
+
+		git pack-objects test2 --stdin-packs --unpacked <<-EOF &&
+		$PACK_A
+		^$PACK_B
+		$PACK_C
+		EOF
+
+		(
+			git show-index <$(ls .git/objects/pack/pack-A-*.idx) &&
+			git show-index <$(ls .git/objects/pack/pack-C-*.idx) &&
+			git rev-list --objects --no-object-names \
+				refs/tags/C..refs/tags/D
+
+		) >expect.raw &&
+		ls -la . &&
+		git show-index <$(ls test2-*.idx) >actual.raw &&
+
+		cut -d" " -f2 <expect.raw | sort >expect &&
+		cut -d" " -f2 <actual.raw | sort >actual &&
+		test_cmp expect actual
+	)
+'
+
+test_expect_success '--stdin-packs with broken links' '
+	(
+		cd stdin-packs &&
+
+		# make an unreachable object with a bogus parent
+		git cat-file -p HEAD >commit &&
+		sed "s/$(git rev-parse HEAD^)/$(test_oid zero)/" <commit |
+		git hash-object -w -t commit --stdin >in &&
+
+		git pack-objects .git/objects/pack/pack-D <in &&
+
+		PACK_A="$(basename .git/objects/pack/pack-A-*.pack)" &&
+		PACK_B="$(basename .git/objects/pack/pack-B-*.pack)" &&
+		PACK_C="$(basename .git/objects/pack/pack-C-*.pack)" &&
+		PACK_D="$(basename .git/objects/pack/pack-D-*.pack)" &&
+
+		git pack-objects test3 --stdin-packs --unpacked <<-EOF &&
+		$PACK_A
+		^$PACK_B
+		$PACK_C
+		$PACK_D
+		EOF
+
+		(
+			git show-index <$(ls .git/objects/pack/pack-A-*.idx) &&
+			git show-index <$(ls .git/objects/pack/pack-C-*.idx) &&
+			git show-index <$(ls .git/objects/pack/pack-D-*.idx) &&
+			git rev-list --objects --no-object-names \
+				refs/tags/C..refs/tags/D
+		) >expect.raw &&
+		git show-index <$(ls test3-*.idx) >actual.raw &&
+
+		cut -d" " -f2 <expect.raw | sort >expect &&
+		cut -d" " -f2 <actual.raw | sort >actual &&
+		test_cmp expect actual
+	)
+'
+
+test_expect_success 'pack-objects --stdin with duplicate packfile' '
+	test_when_finished "rm -fr repo" &&
+
+	git init repo &&
+	(
+		cd repo &&
+		test_commit "commit" &&
+		git repack -ad &&
+
+		{
+			basename .git/objects/pack/pack-*.pack &&
+			basename .git/objects/pack/pack-*.pack
+		} >packfiles &&
+
+		git pack-objects --stdin-packs generated-pack <packfiles &&
+		packed_objects .git/objects/pack/pack-*.idx >expect &&
+		packed_objects generated-pack-*.idx >actual &&
+		test_cmp expect actual
+	)
+'
+
+test_expect_success 'pack-objects --stdin with same packfile excluded and included' '
+	test_when_finished "rm -fr repo" &&
+
+	git init repo &&
+	(
+		cd repo &&
+		test_commit "commit" &&
+		git repack -ad &&
+
+		{
+			basename .git/objects/pack/pack-*.pack &&
+			printf "^%s\n" "$(basename .git/objects/pack/pack-*.pack)"
+		} >packfiles &&
+
+		git pack-objects --stdin-packs generated-pack <packfiles &&
+		packed_objects generated-pack-*.idx >packed-objects &&
+		test_must_be_empty packed-objects
+	)
+'
+
+test_expect_success 'pack-objects --stdin with packfiles from alternate object database' '
+	test_when_finished "rm -fr shared member" &&
+
+	# Set up a shared repository with a single packfile.
+	git init shared &&
+	test_commit -C shared "shared-objects" &&
+	git -C shared repack -ad &&
+	basename shared/.git/objects/pack/pack-*.pack >packfile &&
+
+	# Set up a repository that is connected to the shared repository. This
+	# repository has no objects on its own, but we still expect to be able
+	# to pack objects from its alternate.
+	git clone --shared shared member &&
+	git -C member pack-objects --stdin-packs generated-pack <packfile &&
+	test_cmp shared/.git/objects/pack/pack-*.pack member/generated-pack-*.pack
+'
+
+test_expect_success 'pack-objects --stdin with packfiles from main and alternate object database' '
+	test_when_finished "rm -fr shared member" &&
+
+	# Set up a shared repository with a single packfile.
+	git init shared &&
+	test_commit -C shared "shared-commit" &&
+	git -C shared repack -ad &&
+
+	# Set up a repository that is connected to the shared repository. This
+	# repository has a second packfile so that we can verify that it is
+	# possible to write packs that include packfiles from different object
+	# databases.
+	git clone --shared shared member &&
+	test_commit -C member "local-commit" &&
+	git -C member repack -dl &&
+
+	{
+		basename shared/.git/objects/pack/pack-*.pack &&
+		basename member/.git/objects/pack/pack-*.pack
+	} >packfiles &&
+
+	{
+		packed_objects shared/.git/objects/pack/pack-*.idx &&
+		packed_objects member/.git/objects/pack/pack-*.idx
+	} | sort >expected-objects &&
+
+	git -C member pack-objects --stdin-packs generated-pack <packfiles &&
+	packed_objects member/generated-pack-*.idx >actual-objects &&
+	test_cmp expected-objects actual-objects
+'
+
+test_done
diff --git a/t/t5512-ls-remote.sh b/t/t5512-ls-remote.sh
index 20d063fb9a..151c76eb09 100755
--- a/t/t5512-ls-remote.sh
+++ b/t/t5512-ls-remote.sh
@@ -15,6 +15,19 @@ generate_references () {
 	done
 }
 
+test_expect_success 'set up fake upload-pack' '
+	# This can be used to simulate an upload-pack that just shows the
+	# contents of the "input" file (prepared with the test-tool pkt-line
+	# helper), and does not do any negotiation (since ls-remote does not
+	# need it).
+	write_script cat-input <<-\EOF
+	# send our initial advertisement/response
+	cat input
+	# soak up the flush packet from the client
+	cat
+	EOF
+'
+
 test_expect_success 'dies when no remote found' '
 	test_must_fail git ls-remote
 '
@@ -231,22 +244,25 @@ test_expect_success 'protocol v2 supports hiderefs' '
 
 test_expect_success 'ls-remote --symref' '
 	git fetch origin &&
-	echo "ref: refs/heads/main	HEAD" >expect &&
+	echo "ref: refs/heads/main	HEAD" >expect.v2 &&
 	generate_references \
 		HEAD \
-		refs/heads/main >>expect &&
+		refs/heads/main >>expect.v2 &&
+	echo "ref: refs/remotes/origin/main	refs/remotes/origin/HEAD" >>expect.v2 &&
 	oid=$(git rev-parse HEAD) &&
-	echo "$oid	refs/remotes/origin/HEAD" >>expect &&
+	echo "$oid	refs/remotes/origin/HEAD" >>expect.v2 &&
 	generate_references \
 		refs/remotes/origin/main \
 		refs/tags/mark \
 		refs/tags/mark1.1 \
 		refs/tags/mark1.10 \
-		refs/tags/mark1.2 >>expect &&
-	# Protocol v2 supports sending symrefs for refs other than HEAD, so use
-	# protocol v0 here.
-	GIT_TEST_PROTOCOL_VERSION=0 git ls-remote --symref >actual &&
-	test_cmp expect actual
+		refs/tags/mark1.2 >>expect.v2 &&
+	# v0 does not show non-HEAD symrefs
+	grep -v "ref: refs/remotes" <expect.v2 >expect.v0 &&
+	git -c protocol.version=0 ls-remote --symref >actual.v0 &&
+	test_cmp expect.v0 actual.v0 &&
+	git -c protocol.version=2 ls-remote --symref >actual.v2 &&
+	test_cmp expect.v2 actual.v2
 '
 
 test_expect_success 'ls-remote with filtered symref (refname)' '
@@ -255,76 +271,41 @@ test_expect_success 'ls-remote with filtered symref (refname)' '
 	ref: refs/heads/main	HEAD
 	$rev	HEAD
 	EOF
-	# Protocol v2 supports sending symrefs for refs other than HEAD, so use
-	# protocol v0 here.
-	GIT_TEST_PROTOCOL_VERSION=0 git ls-remote --symref . HEAD >actual &&
+	git ls-remote --symref . HEAD >actual &&
 	test_cmp expect actual
 '
 
-test_expect_failure 'ls-remote with filtered symref (--heads)' '
+test_expect_success 'ls-remote with filtered symref (--heads)' '
 	git symbolic-ref refs/heads/foo refs/tags/mark &&
-	cat >expect <<-EOF &&
+	cat >expect.v2 <<-EOF &&
 	ref: refs/tags/mark	refs/heads/foo
 	$rev	refs/heads/foo
 	$rev	refs/heads/main
 	EOF
-	# Protocol v2 supports sending symrefs for refs other than HEAD, so use
-	# protocol v0 here.
-	GIT_TEST_PROTOCOL_VERSION=0 git ls-remote --symref --heads . >actual &&
-	test_cmp expect actual
+	grep -v "^ref: refs/tags/" <expect.v2 >expect.v0 &&
+	git -c protocol.version=0 ls-remote --symref --heads . >actual.v0 &&
+	test_cmp expect.v0 actual.v0 &&
+	git -c protocol.version=2 ls-remote --symref --heads . >actual.v2 &&
+	test_cmp expect.v2 actual.v2
 '
 
-test_expect_success 'ls-remote --symref omits filtered-out matches' '
-	cat >expect <<-EOF &&
-	$rev	refs/heads/foo
-	$rev	refs/heads/main
+test_expect_success 'indicate no refs in v0 standards-compliant empty remote' '
+	# Git does not produce an output like this, but it does match the
+	# standard and is produced by other implementations like JGit. So
+	# hard-code the case we care about.
+	#
+	# The actual capabilities do not matter; there are none that would
+	# change how ls-remote behaves.
+	oid=0000000000000000000000000000000000000000 &&
+	test-tool pkt-line pack >input.q <<-EOF &&
+	$oid capabilities^{}Qcaps-go-here
+	0000
 	EOF
-	# Protocol v2 supports sending symrefs for refs other than HEAD, so use
-	# protocol v0 here.
-	GIT_TEST_PROTOCOL_VERSION=0 git ls-remote --symref --heads . >actual &&
-	test_cmp expect actual &&
-	GIT_TEST_PROTOCOL_VERSION=0 git ls-remote --symref . "refs/heads/*" >actual &&
-	test_cmp expect actual
-'
-
-test_lazy_prereq GIT_DAEMON '
-	test_bool_env GIT_TEST_GIT_DAEMON true
-'
+	q_to_nul <input.q >input &&
 
-# This test spawns a daemon, so run it only if the user would be OK with
-# testing with git-daemon.
-test_expect_success PIPE,JGIT,GIT_DAEMON 'indicate no refs in standards-compliant empty remote' '
-	test_set_port JGIT_DAEMON_PORT &&
-	JGIT_DAEMON_PID= &&
-	git init --bare empty.git &&
-	>empty.git/git-daemon-export-ok &&
-	mkfifo jgit_daemon_output &&
-	{
-		jgit daemon --port="$JGIT_DAEMON_PORT" . >jgit_daemon_output &
-		JGIT_DAEMON_PID=$!
-	} &&
-	test_when_finished kill "$JGIT_DAEMON_PID" &&
-	{
-		read line &&
-		case $line in
-		Exporting*)
-			;;
-		*)
-			echo "Expected: Exporting" &&
-			false;;
-		esac &&
-		read line &&
-		case $line in
-		"Listening on"*)
-			;;
-		*)
-			echo "Expected: Listening on" &&
-			false;;
-		esac
-	} <jgit_daemon_output &&
 	# --exit-code asks the command to exit with 2 when no
 	# matching refs are found.
-	test_expect_code 2 git ls-remote --exit-code git://localhost:$JGIT_DAEMON_PORT/empty.git
+	test_expect_code 2 git ls-remote --exit-code --upload-pack=./cat-input .
 '
 
 test_expect_success 'ls-remote works outside repository' '
@@ -345,8 +326,8 @@ test_expect_success 'ls-remote --sort fails gracefully outside repository' '
 test_expect_success 'ls-remote patterns work with all protocol versions' '
 	git for-each-ref --format="%(objectname)	%(refname)" \
 		refs/heads/main refs/remotes/origin/main >expect &&
-	git -c protocol.version=1 ls-remote . main >actual.v1 &&
-	test_cmp expect actual.v1 &&
+	git -c protocol.version=0 ls-remote . main >actual.v0 &&
+	test_cmp expect actual.v0 &&
 	git -c protocol.version=2 ls-remote . main >actual.v2 &&
 	test_cmp expect actual.v2
 '
@@ -354,10 +335,49 @@ test_expect_success 'ls-remote patterns work with all protocol versions' '
 test_expect_success 'ls-remote prefixes work with all protocol versions' '
 	git for-each-ref --format="%(objectname)	%(refname)" \
 		refs/heads/ refs/tags/ >expect &&
-	git -c protocol.version=1 ls-remote --heads --tags . >actual.v1 &&
-	test_cmp expect actual.v1 &&
+	git -c protocol.version=0 ls-remote --heads --tags . >actual.v0 &&
+	test_cmp expect actual.v0 &&
 	git -c protocol.version=2 ls-remote --heads --tags . >actual.v2 &&
 	test_cmp expect actual.v2
 '
 
+test_expect_success 'v0 clients can handle multiple symrefs' '
+	# Modern versions of Git will not return multiple symref capabilities
+	# for v0, so we have to hard-code the response. Note that we will
+	# always use both v0 and object-format=sha1 here, as the hard-coded
+	# response reflects a server that only supports those.
+	oid=1234567890123456789012345678901234567890 &&
+	symrefs="symref=refs/remotes/origin/HEAD:refs/remotes/origin/main" &&
+	symrefs="$symrefs symref=HEAD:refs/heads/main" &&
+
+	# Likewise we want to make sure our parser is not fooled by the string
+	# "symref" appearing as part of an earlier cap. But there is no way to
+	# do that via upload-pack, as arbitrary strings can appear only in a
+	# "symref" value itself (where we skip past the values as a whole)
+	# and "agent" (which always appears after "symref", so putting our
+	# parser in a confused state is less interesting).
+	caps="some other caps including a-fake-symref-cap" &&
+
+	test-tool pkt-line pack >input.q <<-EOF &&
+	$oid HEADQ$caps $symrefs
+	$oid refs/heads/main
+	$oid refs/remotes/origin/HEAD
+	$oid refs/remotes/origin/main
+	0000
+	EOF
+	q_to_nul <input.q >input &&
+
+	cat >expect <<-EOF &&
+	ref: refs/heads/main	HEAD
+	$oid	HEAD
+	$oid	refs/heads/main
+	ref: refs/remotes/origin/main	refs/remotes/origin/HEAD
+	$oid	refs/remotes/origin/HEAD
+	$oid	refs/remotes/origin/main
+	EOF
+
+	git ls-remote --symref --upload-pack=./cat-input . >actual &&
+	test_cmp expect actual
+'
+
 test_done
diff --git a/t/t6500-gc.sh b/t/t6500-gc.sh
index d9acb63951..69509d0c11 100755
--- a/t/t6500-gc.sh
+++ b/t/t6500-gc.sh
@@ -210,90 +210,95 @@ prepare_cruft_history () {
 	git reset HEAD^^
 }
 
-assert_cruft_packs () {
-	find .git/objects/pack -name "*.mtimes" >mtimes &&
-	sed -e 's/\.mtimes$/\.pack/g' mtimes >packs &&
-
-	test_file_not_empty packs &&
-	while read pack
-	do
-		test_path_is_file "$pack" || return 1
-	done <packs
-}
-
 assert_no_cruft_packs () {
 	find .git/objects/pack -name "*.mtimes" >mtimes &&
 	test_must_be_empty mtimes
 }
 
-test_expect_success 'gc --cruft generates a cruft pack' '
-	test_when_finished "rm -fr crufts" &&
-	git init crufts &&
+for argv in \
+	"gc" \
+	"-c gc.cruftPacks=true gc" \
+	"-c gc.cruftPacks=false gc --cruft"
+do
+	test_expect_success "git $argv generates a cruft pack" '
+		test_when_finished "rm -fr repo" &&
+		git init repo &&
+		(
+			cd repo &&
+
+			prepare_cruft_history &&
+			git $argv &&
+
+			find .git/objects/pack -name "*.mtimes" >mtimes &&
+			sed -e 's/\.mtimes$/\.pack/g' mtimes >packs &&
+
+			test_file_not_empty packs &&
+			while read pack
+			do
+				test_path_is_file "$pack" || return 1
+			done <packs
+		)
+	'
+done
+
+for argv in \
+	"gc --no-cruft" \
+	"-c gc.cruftPacks=false gc" \
+	"-c gc.cruftPacks=true gc --no-cruft"
+do
+	test_expect_success "git $argv does not generate a cruft pack" '
+		test_when_finished "rm -fr repo" &&
+		git init repo &&
+		(
+			cd repo &&
+
+			prepare_cruft_history &&
+			git $argv &&
+
+			assert_no_cruft_packs
+		)
+	'
+done
+
+test_expect_success '--keep-largest-pack ignores cruft packs' '
+	test_when_finished "rm -fr repo" &&
+	git init repo &&
 	(
-		cd crufts &&
+		cd repo &&
 
+		# Generate a pack for reachable objects (of which there
+		# are 3), and one for unreachable objects (of which
+		# there are 6).
 		prepare_cruft_history &&
 		git gc --cruft &&
-		assert_cruft_packs
-	)
-'
-
-test_expect_success 'gc.cruftPacks=true generates a cruft pack' '
-	test_when_finished "rm -fr crufts" &&
-	git init crufts &&
-	(
-		cd crufts &&
-
-		prepare_cruft_history &&
-		git -c gc.cruftPacks=true gc &&
-		assert_cruft_packs
-	)
-'
-
-test_expect_success 'feature.experimental=true generates a cruft pack' '
-	git init crufts &&
-	test_when_finished "rm -fr crufts" &&
-	(
-		cd crufts &&
 
-		prepare_cruft_history &&
-		git -c feature.experimental=true gc &&
-		assert_cruft_packs
-	)
-'
+		mtimes="$(find .git/objects/pack -type f -name "pack-*.mtimes")" &&
+		sz="$(test_file_size "${mtimes%.mtimes}.pack")" &&
 
-test_expect_success 'feature.experimental=false allows explicit cruft packs' '
-	git init crufts &&
-	test_when_finished "rm -fr crufts" &&
-	(
-		cd crufts &&
+		# Ensure that the cruft pack gets removed (due to
+		# `--prune=now`) despite it being the largest pack.
+		git -c gc.bigPackThreshold=$sz gc --cruft --prune=now &&
 
-		prepare_cruft_history &&
-		git -c gc.cruftPacks=true -c feature.experimental=false gc &&
-		assert_cruft_packs
+		assert_no_cruft_packs
 	)
 '
 
-test_expect_success 'feature.experimental=true can be overridden' '
-	git init crufts &&
-	test_when_finished "rm -fr crufts" &&
+test_expect_success 'gc.bigPackThreshold ignores cruft packs' '
+	test_when_finished "rm -fr repo" &&
+	git init repo &&
 	(
-		cd crufts &&
+		cd repo &&
 
+		# Generate a pack for reachable objects (of which there
+		# are 3), and one for unreachable objects (of which
+		# there are 6).
 		prepare_cruft_history &&
-		git -c feature.expiremental=true -c gc.cruftPacks=false gc &&
-		assert_no_cruft_packs
-	)
-'
+		git gc --cruft &&
 
-test_expect_success 'feature.experimental=false avoids cruft packs by default' '
-	git init crufts &&
-	test_when_finished "rm -fr crufts" &&
-	(
-		cd crufts &&
+		# Ensure that the cruft pack gets removed (due to
+		# `--prune=now`) despite it being the largest pack.
+		git gc --cruft --prune=now --keep-largest-pack &&
 
-		prepare_cruft_history &&
-		git -c feature.experimental=false gc &&
 		assert_no_cruft_packs
 	)
 '
diff --git a/t/t6501-freshen-objects.sh b/t/t6501-freshen-objects.sh
index 3968b47ed5..dbfa8a4d4c 100755
--- a/t/t6501-freshen-objects.sh
+++ b/t/t6501-freshen-objects.sh
@@ -101,7 +101,7 @@ do
 	'
 
 	test_expect_success "simultaneous gc ($title)" '
-		git gc --prune=12.hours.ago
+		git gc --no-cruft --prune=12.hours.ago
 	'
 
 	test_expect_success "finish writing out commit ($title)" '
@@ -131,7 +131,7 @@ do
 	'
 
 	test_expect_success "simultaneous gc ($title)" '
-		git gc --prune=12.hours.ago
+		git gc --no-cruft --prune=12.hours.ago
 	'
 
 	# tree should have been refreshed by write-tree
@@ -151,7 +151,7 @@ test_expect_success 'do not complain about existing broken links (commit)' '
 	some message
 	EOF
 	commit=$(git hash-object -t commit -w broken-commit) &&
-	git gc -q 2>stderr &&
+	git gc --no-cruft -q 2>stderr &&
 	verbose git cat-file -e $commit &&
 	test_must_be_empty stderr
 '
@@ -161,7 +161,7 @@ test_expect_success 'do not complain about existing broken links (tree)' '
 	100644 blob $(test_oid 003)	foo
 	EOF
 	tree=$(git mktree --missing <broken-tree) &&
-	git gc -q 2>stderr &&
+	git gc --no-cruft -q 2>stderr &&
 	git cat-file -e $tree &&
 	test_must_be_empty stderr
 '
@@ -176,7 +176,7 @@ test_expect_success 'do not complain about existing broken links (tag)' '
 	this is a broken tag
 	EOF
 	tag=$(git hash-object -t tag -w broken-tag) &&
-	git gc -q 2>stderr &&
+	git gc --no-cruft -q 2>stderr &&
 	git cat-file -e $tag &&
 	test_must_be_empty stderr
 '
diff --git a/t/t7510-signed-commit.sh b/t/t7510-signed-commit.sh
index 48f86cb367..ccbc416402 100755
--- a/t/t7510-signed-commit.sh
+++ b/t/t7510-signed-commit.sh
@@ -221,84 +221,91 @@ test_expect_success GPG 'amending already signed commit' '
 test_expect_success GPG 'show good signature with custom format' '
 	cat >expect <<-\EOF &&
 	G
+	ultimate
 	13B6F51ECDDE430D
 	C O Mitter <committer@example.com>
 	73D758744BE721698EC54E8713B6F51ECDDE430D
 	73D758744BE721698EC54E8713B6F51ECDDE430D
 	EOF
-	git log -1 --format="%G?%n%GK%n%GS%n%GF%n%GP" sixth-signed >actual &&
+	git log -1 --format="%G?%n%GT%n%GK%n%GS%n%GF%n%GP" sixth-signed >actual &&
 	test_cmp expect actual
 '
 
 test_expect_success GPG 'show bad signature with custom format' '
 	cat >expect <<-\EOF &&
 	B
+	undefined
 	13B6F51ECDDE430D
 	C O Mitter <committer@example.com>
 
 
 	EOF
-	git log -1 --format="%G?%n%GK%n%GS%n%GF%n%GP" $(cat forged1.commit) >actual &&
+	git log -1 --format="%G?%n%GT%n%GK%n%GS%n%GF%n%GP" $(cat forged1.commit) >actual &&
 	test_cmp expect actual
 '
 
 test_expect_success GPG 'show untrusted signature with custom format' '
 	cat >expect <<-\EOF &&
 	U
+	undefined
 	65A0EEA02E30CAD7
 	Eris Discordia <discord@example.net>
 	F8364A59E07FFE9F4D63005A65A0EEA02E30CAD7
 	D4BE22311AD3131E5EDA29A461092E85B7227189
 	EOF
-	git log -1 --format="%G?%n%GK%n%GS%n%GF%n%GP" eighth-signed-alt >actual &&
+	git log -1 --format="%G?%n%GT%n%GK%n%GS%n%GF%n%GP" eighth-signed-alt >actual &&
 	test_cmp expect actual
 '
 
 test_expect_success GPG 'show untrusted signature with undefined trust level' '
 	cat >expect <<-\EOF &&
+	U
 	undefined
 	65A0EEA02E30CAD7
 	Eris Discordia <discord@example.net>
 	F8364A59E07FFE9F4D63005A65A0EEA02E30CAD7
 	D4BE22311AD3131E5EDA29A461092E85B7227189
 	EOF
-	git log -1 --format="%GT%n%GK%n%GS%n%GF%n%GP" eighth-signed-alt >actual &&
+	git log -1 --format="%G?%n%GT%n%GK%n%GS%n%GF%n%GP" eighth-signed-alt >actual &&
 	test_cmp expect actual
 '
 
 test_expect_success GPG 'show untrusted signature with ultimate trust level' '
 	cat >expect <<-\EOF &&
+	G
 	ultimate
 	13B6F51ECDDE430D
 	C O Mitter <committer@example.com>
 	73D758744BE721698EC54E8713B6F51ECDDE430D
 	73D758744BE721698EC54E8713B6F51ECDDE430D
 	EOF
-	git log -1 --format="%GT%n%GK%n%GS%n%GF%n%GP" sixth-signed >actual &&
+	git log -1 --format="%G?%n%GT%n%GK%n%GS%n%GF%n%GP" sixth-signed >actual &&
 	test_cmp expect actual
 '
 
 test_expect_success GPG 'show unknown signature with custom format' '
 	cat >expect <<-\EOF &&
 	E
+	undefined
 	65A0EEA02E30CAD7
 
 
 
 	EOF
-	GNUPGHOME="$GNUPGHOME_NOT_USED" git log -1 --format="%G?%n%GK%n%GS%n%GF%n%GP" eighth-signed-alt >actual &&
+	GNUPGHOME="$GNUPGHOME_NOT_USED" git log -1 --format="%G?%n%GT%n%GK%n%GS%n%GF%n%GP" eighth-signed-alt >actual &&
 	test_cmp expect actual
 '
 
 test_expect_success GPG 'show lack of signature with custom format' '
 	cat >expect <<-\EOF &&
 	N
+	undefined
 
 
 
 
 	EOF
-	git log -1 --format="%G?%n%GK%n%GS%n%GF%n%GP" seventh-unsigned >actual &&
+	git log -1 --format="%G?%n%GT%n%GK%n%GS%n%GF%n%GP" seventh-unsigned >actual &&
 	test_cmp expect actual
 '
 
diff --git a/t/t7700-repack.sh b/t/t7700-repack.sh
index 4aabe98139..faa739eeb9 100755
--- a/t/t7700-repack.sh
+++ b/t/t7700-repack.sh
@@ -106,6 +106,23 @@ test_expect_success SYMLINKS '--local keeps packs when alternate is objectdir '
 	test_cmp expect actual
 '
 
+test_expect_success '--local disables writing bitmaps when connected to alternate ODB' '
+	test_when_finished "rm -rf shared member" &&
+
+	git init shared &&
+	git clone --shared shared member &&
+	(
+		cd member &&
+		test_commit "object" &&
+		GIT_TEST_MULTI_PACK_INDEX=0 git repack -Adl --write-bitmap-index 2>err &&
+		cat >expect <<-EOF &&
+		warning: disabling bitmap writing, as some objects are not being packed
+		EOF
+		test_cmp expect err &&
+		test_path_is_missing .git/objects/pack-*.bitmap
+	)
+'
+
 test_expect_success 'packed obs in alt ODB are repacked even when local repo is packless' '
 	mkdir alt_objects/pack &&
 	mv .git/objects/pack/* alt_objects/pack &&
diff --git a/t/t7703-repack-geometric.sh b/t/t7703-repack-geometric.sh
index 8821fbd2dd..00f28fb558 100755
--- a/t/t7703-repack-geometric.sh
+++ b/t/t7703-repack-geometric.sh
@@ -10,6 +10,12 @@ objdir=.git/objects
 packdir=$objdir/pack
 midx=$objdir/pack/multi-pack-index
 
+packed_objects () {
+	git show-index <"$1" >tmp-object-list &&
+	cut -d' ' -f2 tmp-object-list | sort &&
+	rm tmp-object-list
+ }
+
 test_expect_success '--geometric with no packs' '
 	git init geometric &&
 	test_when_finished "rm -fr geometric" &&
@@ -281,4 +287,162 @@ test_expect_success '--geometric with pack.packSizeLimit' '
 	)
 '
 
+test_expect_success '--geometric --write-midx with packfiles in main and alternate ODB' '
+	test_when_finished "rm -fr shared member" &&
+
+	# Create a shared repository that will serve as the alternate object
+	# database for the member linked to it. It has got some objects on its
+	# own that are packed into a single packfile.
+	git init shared &&
+	test_commit -C shared common-object &&
+	git -C shared repack -ad &&
+
+	# We create member so that its alternates file points to the shared
+	# repository. We then create a commit in it so that git-repack(1) has
+	# something to repack.
+	# of the shared object database.
+	git clone --shared shared member &&
+	test_commit -C member unique-object &&
+	git -C member repack --geometric=2 --write-midx 2>err &&
+	test_must_be_empty err &&
+
+	# We should see that a new packfile was generated.
+	find shared/.git/objects/pack -type f -name "*.pack" >packs &&
+	test_line_count = 1 packs &&
+
+	# We should also see a multi-pack-index. This multi-pack-index should
+	# never refer to any packfiles in the alternate object database.
+	test_path_is_file member/.git/objects/pack/multi-pack-index &&
+	test-tool read-midx member/.git/objects >packs.midx &&
+	grep "^pack-.*\.idx$" packs.midx | sort >actual &&
+	basename member/.git/objects/pack/pack-*.idx >expect &&
+	test_cmp expect actual
+'
+
+test_expect_success '--geometric --with-midx with no local objects' '
+	test_when_finished "rm -fr shared member" &&
+
+	# Create a repository with a single packfile that acts as alternate
+	# object database.
+	git init shared &&
+	test_commit -C shared "shared-objects" &&
+	git -C shared repack -ad &&
+
+	# Create a second repository linked to the first one and perform a
+	# geometric repack on it.
+	git clone --shared shared member &&
+	git -C member repack --geometric 2 --write-midx 2>err &&
+	test_must_be_empty err &&
+
+	# Assert that we wrote neither a new packfile nor a multi-pack-index.
+	# We should not have a packfile because the single packfile in the
+	# alternate object database does not invalidate the geometric sequence.
+	# And we should not have a multi-pack-index because these only index
+	# local packfiles, and there are none.
+	test_dir_is_empty member/$packdir
+'
+
+test_expect_success '--geometric with same pack in main and alternate ODB' '
+	test_when_finished "rm -fr shared member" &&
+
+	# Create a repository with a single packfile that acts as alternate
+	# object database.
+	git init shared &&
+	test_commit -C shared "shared-objects" &&
+	git -C shared repack -ad &&
+
+	# We create the member repository as an exact copy so that it has the
+	# same packfile.
+	cp -r shared member &&
+	test-tool path-utils real_path shared/.git/objects >member/.git/objects/info/alternates &&
+	find shared/.git/objects -type f >expected-files &&
+
+	# Verify that we can repack objects as expected without observing any
+	# error. Having the same packfile in both ODBs used to cause an error
+	# in git-pack-objects(1).
+	git -C member repack --geometric 2 2>err &&
+	test_must_be_empty err &&
+	# Nothing should have changed.
+	find shared/.git/objects -type f >actual-files &&
+	test_cmp expected-files actual-files
+'
+
+test_expect_success '--geometric -l with non-intact geometric sequence across ODBs' '
+	test_when_finished "rm -fr shared member" &&
+
+	git init shared &&
+	test_commit_bulk -C shared --start=1 1 &&
+
+	git clone --shared shared member &&
+	test_commit_bulk -C member --start=2 1 &&
+
+	# Verify that our assumptions actually hold: both generated packfiles
+	# should have three objects and should be non-equal.
+	packed_objects shared/.git/objects/pack/pack-*.idx >shared-objects &&
+	packed_objects member/.git/objects/pack/pack-*.idx >member-objects &&
+	test_line_count = 3 shared-objects &&
+	test_line_count = 3 member-objects &&
+	! test_cmp shared-objects member-objects &&
+
+	# Perform the geometric repack. With `-l`, we should only see the local
+	# packfile and thus arrive at the conclusion that the geometric
+	# sequence is intact. We thus expect no changes.
+	#
+	# Note that we are tweaking mtimes of the packfiles so that we can
+	# verify they did not change. This is done in order to detect the case
+	# where we do repack objects, but the resulting packfile is the same.
+	test-tool chmtime --verbose =0 member/.git/objects/pack/* >expected-member-packs &&
+	git -C member repack --geometric=2 -l -d &&
+	test-tool chmtime --verbose member/.git/objects/pack/* >actual-member-packs &&
+	test_cmp expected-member-packs actual-member-packs &&
+
+	{
+		packed_objects shared/.git/objects/pack/pack-*.idx &&
+		packed_objects member/.git/objects/pack/pack-*.idx
+	} | sort >expected-objects &&
+
+	# On the other hand, when doing a non-local geometric repack we should
+	# see both packfiles and thus repack them. We expect that the shared
+	# object database was not changed.
+	test-tool chmtime --verbose =0 shared/.git/objects/pack/* >expected-shared-packs &&
+	git -C member repack --geometric=2 -d &&
+	test-tool chmtime --verbose shared/.git/objects/pack/* >actual-shared-packs &&
+	test_cmp expected-shared-packs actual-shared-packs &&
+
+	# Furthermore, we expect that the member repository now has a single
+	# packfile that contains the combined shared and non-shared objects.
+	ls member/.git/objects/pack/pack-*.idx >actual &&
+	test_line_count = 1 actual &&
+	packed_objects member/.git/objects/pack/pack-*.idx >actual-objects &&
+	test_line_count = 6 actual-objects &&
+	test_cmp expected-objects actual-objects
+'
+
+test_expect_success '--geometric -l disables writing bitmaps with non-local packfiles' '
+	test_when_finished "rm -fr shared member" &&
+
+	git init shared &&
+	test_commit_bulk -C shared --start=1 1 &&
+
+	git clone --shared shared member &&
+	test_commit_bulk -C member --start=2 1 &&
+
+	# When performing a geometric repack with `-l` while connected to an
+	# alternate object database that has a packfile we do not have full
+	# coverage of objects. As a result, we expect that writing the bitmap
+	# will be disabled.
+	git -C member repack -l --geometric=2 --write-midx --write-bitmap-index 2>err &&
+	cat >expect <<-EOF &&
+	warning: disabling bitmap writing, as some objects are not being packed
+	EOF
+	test_cmp expect err &&
+	test_path_is_missing member/.git/objects/pack/multi-pack-index-*.bitmap &&
+
+	# On the other hand, when we repack without `-l`, we should see that
+	# the bitmap gets created.
+	git -C member repack --geometric=2 --write-midx --write-bitmap-index 2>err &&
+	test_must_be_empty err &&
+	test_path_is_file member/.git/objects/pack/multi-pack-index-*.bitmap
+'
+
 test_done
diff --git a/t/t9001-send-email.sh b/t/t9001-send-email.sh
index 0de83b5d2b..6520346246 100755
--- a/t/t9001-send-email.sh
+++ b/t/t9001-send-email.sh
@@ -2326,6 +2326,37 @@ test_expect_success $PREREQ 'invoke hook' '
 	)
 '
 
+expected_file_counter_output () {
+	total=$1
+	count=0
+	while test $count -ne $total
+	do
+		count=$((count + 1)) &&
+		echo "$count/$total" || return
+	done
+}
+
+test_expect_success $PREREQ '--validate hook allows counting of messages' '
+	test_when_finished "rm -rf my-hooks.log" &&
+	test_config core.hooksPath "my-hooks" &&
+	mkdir -p my-hooks &&
+
+	write_script my-hooks/sendemail-validate <<-\EOF &&
+		num=$GIT_SENDEMAIL_FILE_COUNTER &&
+		tot=$GIT_SENDEMAIL_FILE_TOTAL &&
+		echo "$num/$tot" >>my-hooks.log || exit 1
+	EOF
+
+	>my-hooks.log &&
+	expected_file_counter_output 4 >expect &&
+	git send-email \
+		--from="Example <from@example.com>" \
+		--to=nobody@example.com \
+		--smtp-server="$(pwd)/fake.sendmail" \
+		--validate -3 --cover-letter --force &&
+	test_cmp expect my-hooks.log
+'
+
 test_expect_success $PREREQ 'test that send-email works outside a repo' '
 	nongit git send-email \
 		--from="Example <nobody@example.com>" \
diff --git a/t/t9300-fast-import.sh b/t/t9300-fast-import.sh
index aa55b41b9a..ac237a1f90 100755
--- a/t/t9300-fast-import.sh
+++ b/t/t9300-fast-import.sh
@@ -388,9 +388,7 @@ test_expect_success 'B: accept branch name "TEMP_TAG"' '
 
 	INPUT_END
 
-	test_when_finished "rm -f .git/TEMP_TAG
-		git gc
-		git prune" &&
+	test_when_finished "rm -f .git/TEMP_TAG && git gc --prune=now" &&
 	git fast-import <input &&
 	test $(test-tool ref-store main resolve-ref TEMP_TAG 0 | cut -f1 -d " " ) != "$ZERO_OID" &&
 	test $(git rev-parse main) = $(git rev-parse TEMP_TAG^)
@@ -406,8 +404,7 @@ test_expect_success 'B: accept empty committer' '
 	INPUT_END
 
 	test_when_finished "git update-ref -d refs/heads/empty-committer-1
-		git gc
-		git prune" &&
+		git gc --prune=now" &&
 	git fast-import <input &&
 	out=$(git fsck) &&
 	echo "$out" &&
@@ -452,8 +449,7 @@ test_expect_success 'B: accept and fixup committer with no name' '
 	INPUT_END
 
 	test_when_finished "git update-ref -d refs/heads/empty-committer-2
-		git gc
-		git prune" &&
+		git gc --prune=now" &&
 	git fast-import <input &&
 	out=$(git fsck) &&
 	echo "$out" &&
@@ -1778,8 +1774,7 @@ test_expect_success 'P: verbatim SHA gitlinks' '
 	INPUT_END
 
 	git branch -D sub &&
-	git gc &&
-	git prune &&
+	git gc --prune=now &&
 	git fast-import <input &&
 	test $(git rev-parse --verify subuse2) = $(git rev-parse --verify subuse1)
 '