1 files changed, 475 insertions, 0 deletions
diff --git a/t/t0600-reffiles-backend.sh b/t/t0600-reffiles-backend.sh
new file mode 100755
index 0000000..6421434
--- /dev/null
+++ b/t/t0600-reffiles-backend.sh
@@ -0,0 +1,475 @@
+#!/bin/sh
+
+test_description='Test reffiles backend'
+
+GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
+export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
+
+TEST_PASSES_SANITIZE_LEAK=true
+. ./test-lib.sh
+
+if ! test_have_prereq REFFILES
+then
+	skip_all='skipping reffiles specific tests'
+	test_done
+fi
+
+test_expect_success 'setup' '
+	git commit --allow-empty -m Initial &&
+	C=$(git rev-parse HEAD) &&
+	git commit --allow-empty -m Second &&
+	D=$(git rev-parse HEAD) &&
+	git commit --allow-empty -m Third &&
+	E=$(git rev-parse HEAD)
+'
+
+test_expect_success 'empty directory should not fool rev-parse' '
+	prefix=refs/e-rev-parse &&
+	git update-ref $prefix/foo $C &&
+	git pack-refs --all &&
+	mkdir -p .git/$prefix/foo/bar/baz &&
+	echo "$C" >expected &&
+	git rev-parse $prefix/foo >actual &&
+	test_cmp expected actual
+'
+
+test_expect_success 'empty directory should not fool for-each-ref' '
+	prefix=refs/e-for-each-ref &&
+	git update-ref $prefix/foo $C &&
+	git for-each-ref $prefix >expected &&
+	git pack-refs --all &&
+	mkdir -p .git/$prefix/foo/bar/baz &&
+	git for-each-ref $prefix >actual &&
+	test_cmp expected actual
+'
+
+test_expect_success 'empty directory should not fool create' '
+	prefix=refs/e-create &&
+	mkdir -p .git/$prefix/foo/bar/baz &&
+	printf "create %s $C\n" $prefix/foo |
+	git update-ref --stdin
+'
+
+test_expect_success 'empty directory should not fool verify' '
+	prefix=refs/e-verify &&
+	git update-ref $prefix/foo $C &&
+	git pack-refs --all &&
+	mkdir -p .git/$prefix/foo/bar/baz &&
+	printf "verify %s $C\n" $prefix/foo |
+	git update-ref --stdin
+'
+
+test_expect_success 'empty directory should not fool 1-arg update' '
+	prefix=refs/e-update-1 &&
+	git update-ref $prefix/foo $C &&
+	git pack-refs --all &&
+	mkdir -p .git/$prefix/foo/bar/baz &&
+	printf "update %s $D\n" $prefix/foo |
+	git update-ref --stdin
+'
+
+test_expect_success 'empty directory should not fool 2-arg update' '
+	prefix=refs/e-update-2 &&
+	git update-ref $prefix/foo $C &&
+	git pack-refs --all &&
+	mkdir -p .git/$prefix/foo/bar/baz &&
+	printf "update %s $D $C\n" $prefix/foo |
+	git update-ref --stdin
+'
+
+test_expect_success 'empty directory should not fool 0-arg delete' '
+	prefix=refs/e-delete-0 &&
+	git update-ref $prefix/foo $C &&
+	git pack-refs --all &&
+	mkdir -p .git/$prefix/foo/bar/baz &&
+	printf "delete %s\n" $prefix/foo |
+	git update-ref --stdin
+'
+
+test_expect_success 'empty directory should not fool 1-arg delete' '
+	prefix=refs/e-delete-1 &&
+	git update-ref $prefix/foo $C &&
+	git pack-refs --all &&
+	mkdir -p .git/$prefix/foo/bar/baz &&
+	printf "delete %s $C\n" $prefix/foo |
+	git update-ref --stdin
+'
+
+test_expect_success 'non-empty directory blocks create' '
+	prefix=refs/ne-create &&
+	mkdir -p .git/$prefix/foo/bar &&
+	: >.git/$prefix/foo/bar/baz.lock &&
+	test_when_finished "rm -f .git/$prefix/foo/bar/baz.lock" &&
+	cat >expected <<-EOF &&
+	fatal: cannot lock ref $SQ$prefix/foo$SQ: there is a non-empty directory $SQ.git/$prefix/foo$SQ blocking reference $SQ$prefix/foo$SQ
+	EOF
+	printf "%s\n" "update $prefix/foo $C" |
+	test_must_fail git update-ref --stdin 2>output.err &&
+	test_cmp expected output.err &&
+	cat >expected <<-EOF &&
+	fatal: cannot lock ref $SQ$prefix/foo$SQ: unable to resolve reference $SQ$prefix/foo$SQ
+	EOF
+	printf "%s\n" "update $prefix/foo $D $C" |
+	test_must_fail git update-ref --stdin 2>output.err &&
+	test_cmp expected output.err
+'
+
+test_expect_success 'broken reference blocks create' '
+	prefix=refs/broken-create &&
+	mkdir -p .git/$prefix &&
+	echo "gobbledigook" >.git/$prefix/foo &&
+	test_when_finished "rm -f .git/$prefix/foo" &&
+	cat >expected <<-EOF &&
+	fatal: cannot lock ref $SQ$prefix/foo$SQ: unable to resolve reference $SQ$prefix/foo$SQ: reference broken
+	EOF
+	printf "%s\n" "update $prefix/foo $C" |
+	test_must_fail git update-ref --stdin 2>output.err &&
+	test_cmp expected output.err &&
+	cat >expected <<-EOF &&
+	fatal: cannot lock ref $SQ$prefix/foo$SQ: unable to resolve reference $SQ$prefix/foo$SQ: reference broken
+	EOF
+	printf "%s\n" "update $prefix/foo $D $C" |
+	test_must_fail git update-ref --stdin 2>output.err &&
+	test_cmp expected output.err
+'
+
+test_expect_success 'non-empty directory blocks indirect create' '
+	prefix=refs/ne-indirect-create &&
+	git symbolic-ref $prefix/symref $prefix/foo &&
+	mkdir -p .git/$prefix/foo/bar &&
+	: >.git/$prefix/foo/bar/baz.lock &&
+	test_when_finished "rm -f .git/$prefix/foo/bar/baz.lock" &&
+	cat >expected <<-EOF &&
+	fatal: cannot lock ref $SQ$prefix/symref$SQ: there is a non-empty directory $SQ.git/$prefix/foo$SQ blocking reference $SQ$prefix/foo$SQ
+	EOF
+	printf "%s\n" "update $prefix/symref $C" |
+	test_must_fail git update-ref --stdin 2>output.err &&
+	test_cmp expected output.err &&
+	cat >expected <<-EOF &&
+	fatal: cannot lock ref $SQ$prefix/symref$SQ: unable to resolve reference $SQ$prefix/foo$SQ
+	EOF
+	printf "%s\n" "update $prefix/symref $D $C" |
+	test_must_fail git update-ref --stdin 2>output.err &&
+	test_cmp expected output.err
+'
+
+test_expect_success 'broken reference blocks indirect create' '
+	prefix=refs/broken-indirect-create &&
+	git symbolic-ref $prefix/symref $prefix/foo &&
+	echo "gobbledigook" >.git/$prefix/foo &&
+	test_when_finished "rm -f .git/$prefix/foo" &&
+	cat >expected <<-EOF &&
+	fatal: cannot lock ref $SQ$prefix/symref$SQ: unable to resolve reference $SQ$prefix/foo$SQ: reference broken
+	EOF
+	printf "%s\n" "update $prefix/symref $C" |
+	test_must_fail git update-ref --stdin 2>output.err &&
+	test_cmp expected output.err &&
+	cat >expected <<-EOF &&
+	fatal: cannot lock ref $SQ$prefix/symref$SQ: unable to resolve reference $SQ$prefix/foo$SQ: reference broken
+	EOF
+	printf "%s\n" "update $prefix/symref $D $C" |
+	test_must_fail git update-ref --stdin 2>output.err &&
+	test_cmp expected output.err
+'
+
+test_expect_success 'no bogus intermediate values during delete' '
+	prefix=refs/slow-transaction &&
+	# Set up a reference with differing loose and packed versions:
+	git update-ref $prefix/foo $C &&
+	git pack-refs --all &&
+	git update-ref $prefix/foo $D &&
+	# Now try to update the reference, but hold the `packed-refs` lock
+	# for a while to see what happens while the process is blocked:
+	: >.git/packed-refs.lock &&
+	test_when_finished "rm -f .git/packed-refs.lock" &&
+	{
+		# Note: the following command is intentionally run in the
+		# background. We increase the timeout so that `update-ref`
+		# attempts to acquire the `packed-refs` lock for much longer
+		# than it takes for us to do the check then delete it:
+		git -c core.packedrefstimeout=30000 update-ref -d $prefix/foo &
+	} &&
+	pid2=$! &&
+	# Give update-ref plenty of time to get to the point where it tries
+	# to lock packed-refs:
+	sleep 1 &&
+	# Make sure that update-ref did not complete despite the lock:
+	kill -0 $pid2 &&
+	# Verify that the reference still has its old value:
+	sha1=$(git rev-parse --verify --quiet $prefix/foo || echo undefined) &&
+	case "$sha1" in
+	$D)
+		# This is what we hope for; it means that nothing
+		# user-visible has changed yet.
+		: ;;
+	undefined)
+		# This is not correct; it means the deletion has happened
+		# already even though update-ref should not have been
+		# able to acquire the lock yet.
+		echo "$prefix/foo deleted prematurely" &&
+		break
+		;;
+	$C)
+		# This value should never be seen. Probably the loose
+		# reference has been deleted but the packed reference
+		# is still there:
+		echo "$prefix/foo incorrectly observed to be C" &&
+		break
+		;;
+	*)
+		# WTF?
+		echo "unexpected value observed for $prefix/foo: $sha1" &&
+		break
+		;;
+	esac >out &&
+	rm -f .git/packed-refs.lock &&
+	wait $pid2 &&
+	test_must_be_empty out &&
+	test_must_fail git rev-parse --verify --quiet $prefix/foo
+'
+
+test_expect_success 'delete fails cleanly if packed-refs file is locked' '
+	prefix=refs/locked-packed-refs &&
+	# Set up a reference with differing loose and packed versions:
+	git update-ref $prefix/foo $C &&
+	git pack-refs --all &&
+	git update-ref $prefix/foo $D &&
+	git for-each-ref $prefix >unchanged &&
+	# Now try to delete it while the `packed-refs` lock is held:
+	: >.git/packed-refs.lock &&
+	test_when_finished "rm -f .git/packed-refs.lock" &&
+	test_must_fail git update-ref -d $prefix/foo >out 2>err &&
+	git for-each-ref $prefix >actual &&
+	test_grep "Unable to create $SQ.*packed-refs.lock$SQ: " err &&
+	test_cmp unchanged actual
+'
+
+test_expect_success 'delete fails cleanly if packed-refs.new write fails' '
+	# Setup and expectations are similar to the test above.
+	prefix=refs/failed-packed-refs &&
+	git update-ref $prefix/foo $C &&
+	git pack-refs --all &&
+	git update-ref $prefix/foo $D &&
+	git for-each-ref $prefix >unchanged &&
+	# This should not happen in practice, but it is an easy way to get a
+	# reliable error (we open with create_tempfile(), which uses O_EXCL).
+	: >.git/packed-refs.new &&
+	test_when_finished "rm -f .git/packed-refs.new" &&
+	test_must_fail git update-ref -d $prefix/foo &&
+	git for-each-ref $prefix >actual &&
+	test_cmp unchanged actual
+'
+
+RWT="test-tool ref-store worktree:wt"
+RMAIN="test-tool ref-store worktree:main"
+
+test_expect_success 'setup worktree' '
+	test_commit first &&
+	git worktree add -b wt-main wt &&
+	(
+		cd wt &&
+		test_commit second
+	)
+'
+
+# Some refs (refs/bisect/*, pseudorefs) are kept per worktree, so they should
+# only appear in the for-each-reflog output if it is called from the correct
+# worktree, which is exercised in this test. This test is poorly written for
+# mulitple reasons: 1) it creates invalidly formatted log entres. 2) it uses
+# direct FS access for creating the reflogs. 3) PSEUDO-WT and refs/bisect/random
+# do not create reflogs by default, so it is not testing a realistic scenario.
+test_expect_success 'for_each_reflog()' '
+	echo $ZERO_OID >.git/logs/PSEUDO_MAIN_HEAD &&
+	mkdir -p     .git/logs/refs/bisect &&
+	echo $ZERO_OID >.git/logs/refs/bisect/random &&
+
+	echo $ZERO_OID >.git/worktrees/wt/logs/PSEUDO_WT_HEAD &&
+	mkdir -p     .git/worktrees/wt/logs/refs/bisect &&
+	echo $ZERO_OID >.git/worktrees/wt/logs/refs/bisect/wt-random &&
+
+	$RWT for-each-reflog >actual &&
+	cat >expected <<-\EOF &&
+	HEAD
+	PSEUDO_WT_HEAD
+	refs/bisect/wt-random
+	refs/heads/main
+	refs/heads/wt-main
+	EOF
+	test_cmp expected actual &&
+
+	$RMAIN for-each-reflog >actual &&
+	cat >expected <<-\EOF &&
+	HEAD
+	PSEUDO_MAIN_HEAD
+	refs/bisect/random
+	refs/heads/main
+	refs/heads/wt-main
+	EOF
+	test_cmp expected actual
+'
+
+# Triggering the bug detected by this test requires a newline to fall
+# exactly BUFSIZ-1 bytes from the end of the file. We don't know
+# what that value is, since it's platform dependent. However, if
+# we choose some value N, we also catch any D which divides N evenly
+# (since we will read backwards in chunks of D). So we choose 8K,
+# which catches glibc (with an 8K BUFSIZ) and *BSD (1K).
+#
+# Each line is 114 characters, so we need 75 to still have a few before the
+# last 8K. The 89-character padding on the final entry lines up our
+# newline exactly.
+test_expect_success SHA1 'parsing reverse reflogs at BUFSIZ boundaries' '
+	git checkout -b reflogskip &&
+	zf=$(test_oid zero_2) &&
+	ident="abc <xyz> 0000000001 +0000" &&
+	for i in $(test_seq 1 75); do
+		printf "$zf%02d $zf%02d %s\t" $i $(($i+1)) "$ident" &&
+		if test $i = 75; then
+			for j in $(test_seq 1 89); do
+				printf X || return 1
+			done
+		else
+			printf X
+		fi &&
+		printf "\n" || return 1
+	done >.git/logs/refs/heads/reflogskip &&
+	git rev-parse reflogskip@{73} >actual &&
+	echo ${zf}03 >expect &&
+	test_cmp expect actual
+'
+
+# This test takes a lock on an individual ref; this is not supported in
+# reftable.
+test_expect_success 'reflog expire operates on symref not referrent' '
+	git branch --create-reflog the_symref &&
+	git branch --create-reflog referrent &&
+	git update-ref referrent HEAD &&
+	git symbolic-ref refs/heads/the_symref refs/heads/referrent &&
+	test_when_finished "rm -f .git/refs/heads/referrent.lock" &&
+	touch .git/refs/heads/referrent.lock &&
+	git reflog expire --expire=all the_symref
+'
+
+test_expect_success 'empty reflog' '
+	test_when_finished "rm -rf empty" &&
+	git init empty &&
+	test_commit -C empty A &&
+	>empty/.git/logs/refs/heads/foo &&
+	git -C empty reflog expire --all 2>err &&
+	test_must_be_empty err
+'
+
+test_expect_success SYMLINKS 'ref resolution not confused by broken symlinks' '
+       ln -s does-not-exist .git/refs/heads/broken &&
+       test_must_fail git rev-parse --verify broken
+'
+
+test_expect_success 'log diagnoses bogus HEAD hash' '
+	git init empty &&
+	test_when_finished "rm -rf empty" &&
+	echo 1234abcd >empty/.git/refs/heads/main &&
+	test_must_fail git -C empty log 2>stderr &&
+	test_grep broken stderr
+'
+
+test_expect_success 'log diagnoses bogus HEAD symref' '
+	git init empty &&
+	test-tool -C empty ref-store main create-symref HEAD refs/heads/invalid.lock &&
+	test_must_fail git -C empty log 2>stderr &&
+	test_grep broken stderr &&
+	test_must_fail git -C empty log --default totally-bogus 2>stderr &&
+	test_grep broken stderr
+'
+
+test_expect_success 'empty directory removal' '
+	git branch d1/d2/r1 HEAD &&
+	git branch d1/r2 HEAD &&
+	test_path_is_file .git/refs/heads/d1/d2/r1 &&
+	test_path_is_file .git/logs/refs/heads/d1/d2/r1 &&
+	git branch -d d1/d2/r1 &&
+	test_must_fail git show-ref --verify -q refs/heads/d1/d2 &&
+	test_must_fail git show-ref --verify -q logs/refs/heads/d1/d2 &&
+	test_path_is_file .git/refs/heads/d1/r2 &&
+	test_path_is_file .git/logs/refs/heads/d1/r2
+'
+
+test_expect_success 'symref empty directory removal' '
+	git branch e1/e2/r1 HEAD &&
+	git branch e1/r2 HEAD &&
+	git checkout e1/e2/r1 &&
+	test_when_finished "git checkout main" &&
+	test_path_is_file .git/refs/heads/e1/e2/r1 &&
+	test_path_is_file .git/logs/refs/heads/e1/e2/r1 &&
+	git update-ref -d HEAD &&
+	test_must_fail git show-ref --verify -q refs/heads/e1/e2 &&
+	test_must_fail git show-ref --verify -q logs/refs/heads/e1/e2 &&
+	test_path_is_file .git/refs/heads/e1/r2 &&
+	test_path_is_file .git/logs/refs/heads/e1/r2 &&
+	test_path_is_file .git/logs/HEAD
+'
+
+test_expect_success 'directory not created deleting packed ref' '
+	git branch d1/d2/r1 HEAD &&
+	git pack-refs --all &&
+	test_path_is_missing .git/refs/heads/d1/d2 &&
+	git update-ref -d refs/heads/d1/d2/r1 &&
+	test_path_is_missing .git/refs/heads/d1/d2 &&
+	test_path_is_missing .git/refs/heads/d1
+'
+
+test_expect_success SYMLINKS 'git branch -m u v should fail when the reflog for u is a symlink' '
+	git branch --create-reflog u &&
+	mv .git/logs/refs/heads/u real-u &&
+	ln -s real-u .git/logs/refs/heads/u &&
+	test_must_fail git branch -m u v
+'
+
+test_expect_success SYMLINKS 'git branch -m with symlinked .git/refs' '
+	test_when_finished "rm -rf subdir" &&
+	git init --bare subdir &&
+
+	rm -rfv subdir/refs subdir/objects subdir/packed-refs &&
+	ln -s ../.git/refs subdir/refs &&
+	ln -s ../.git/objects subdir/objects &&
+	ln -s ../.git/packed-refs subdir/packed-refs &&
+
+	git -C subdir rev-parse --absolute-git-dir >subdir.dir &&
+	git rev-parse --absolute-git-dir >our.dir &&
+	! test_cmp subdir.dir our.dir &&
+
+	git -C subdir log &&
+	git -C subdir branch rename-src &&
+	git rev-parse rename-src >expect &&
+	git -C subdir branch -m rename-src rename-dest &&
+	git rev-parse rename-dest >actual &&
+	test_cmp expect actual &&
+	git branch -D rename-dest
+'
+
+test_expect_success MINGW,SYMLINKS_WINDOWS 'rebase when .git/logs is a symlink' '
+	git checkout main &&
+	mv .git/logs actual_logs &&
+	cmd //c "mklink /D .git\logs ..\actual_logs" &&
+	git rebase -f HEAD^ &&
+	test -L .git/logs &&
+	rm .git/logs &&
+	mv actual_logs .git/logs
+'
+
+test_expect_success POSIXPERM 'git reflog expire honors core.sharedRepository' '
+	umask 077 &&
+	git config core.sharedRepository group &&
+	git reflog expire --all &&
+	actual="$(ls -l .git/logs/refs/heads/main)" &&
+	case "$actual" in
+	-rw-rw-*)
+		: happy
+		;;
+	*)
+		echo Ooops, .git/logs/refs/heads/main is not 066x [$actual]
+		false
+		;;
+	esac
+'
+
+test_done