From d2986d0f290a065fb8a534fabfff36c40d37ae97 Mon Sep 17 00:00:00 2001
From: Eric Wong <e@80x24.org>
Date: Wed, 25 May 2016 22:54:02 +0000
Subject: fast-import: invalidate pack_id references after loosening

When loosening a pack, the current pack_id gets reused when
checkpointing and the import does not terminate.  This causes
problems after checkpointing as the object table, branch, and
tag lists still contains pre-checkpoint references to the
recycled pack_id.

Merely clearing the object_table as suggested by Jeff King in
http://mid.gmane.org/20160517121330.GA7346@sigill.intra.peff.net
is insufficient as the marks set still contains references
to object entries.

Wrong pack_id references branch and tags lists do not cause
errors, but can lead to misleading crash reports and core dumps,
so they are also invalidated.

Signed-off-by: Eric Wong <e@80x24.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 t/t9302-fast-import-unpack-limit.sh | 57 +++++++++++++++++++++++++++++++++++++
 1 file changed, 57 insertions(+)

(limited to 't/t9302-fast-import-unpack-limit.sh')

diff --git a/t/t9302-fast-import-unpack-limit.sh b/t/t9302-fast-import-unpack-limit.sh
index 0f686d2199..a04de14677 100755
--- a/t/t9302-fast-import-unpack-limit.sh
+++ b/t/t9302-fast-import-unpack-limit.sh
@@ -45,4 +45,61 @@ test_expect_success 'bigger packs are preserved' '
 	test $(find .git/objects/pack -type f | wc -l) -eq 2
 '
 
+test_expect_success 'lookups after checkpoint works' '
+	hello_id=$(echo hello | git hash-object --stdin -t blob) &&
+	id="$GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL> $GIT_COMMITTER_DATE" &&
+	before=$(git rev-parse refs/heads/master^0) &&
+	(
+		cat <<-INPUT_END &&
+		blob
+		mark :1
+		data 6
+		hello
+
+		commit refs/heads/master
+		mark :2
+		committer $id
+		data <<COMMIT
+		checkpoint after this
+		COMMIT
+		from refs/heads/master^0
+		M 100644 :1 hello
+
+		# pre-checkpoint
+		cat-blob :1
+		cat-blob $hello_id
+		checkpoint
+		# post-checkpoint
+		cat-blob :1
+		cat-blob $hello_id
+		INPUT_END
+
+		n=0 &&
+		from=$before &&
+		while test x"$from" = x"$before"
+		do
+			if test $n -gt 30
+			then
+				echo >&2 "checkpoint did not update branch"
+				exit 1
+			else
+				n=$(($n + 1))
+			fi &&
+			sleep 1 &&
+			from=$(git rev-parse refs/heads/master^0)
+		done &&
+		cat <<-INPUT_END &&
+		commit refs/heads/master
+		committer $id
+		data <<COMMIT
+		make sure from "unpacked sha1 reference" works, too
+		COMMIT
+		from $from
+		INPUT_END
+		echo done
+	) | git -c fastimport.unpackLimit=100 fast-import --done &&
+	test $(find .git/objects/?? -type f | wc -l) -eq 6 &&
+	test $(find .git/objects/pack -type f | wc -l) -eq 2
+'
+
 test_done
-- 
cgit v1.2.3