Add --reference option to git submodule.

This adds --reference option to git submodule add and
git submodule update commands, which is passed to git clone.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 81 insertions, 0 deletions

diff --git a/t/t7406-submodule-reference.sh b/t/t7406-submodule-reference.sh
new file mode 100755
index 000000000..cc16d3f05
--- /dev/null
+++ b/t/t7406-submodule-reference.sh
@@ -0,0 +1,81 @@
+#!/bin/sh
+#
+# Copyright (c) 2009, Red Hat Inc, Author: Michael S. Tsirkin (mst@redhat.com)
+#
+
+test_description='test clone --reference'
+. ./test-lib.sh
+
+base_dir=`pwd`
+
+U=$base_dir/UPLOAD_LOG
+
+test_expect_success 'preparing first repository' \
+'test_create_repo A && cd A &&
+echo first > file1 &&
+git add file1 &&
+git commit -m A-initial'
+
+cd "$base_dir"
+
+test_expect_success 'preparing second repository' \
+'git clone A B && cd B &&
+echo second > file2 &&
+git add file2 &&
+git commit -m B-addition &&
+git repack -a -d &&
+git prune'
+
+cd "$base_dir"
+
+test_expect_success 'preparing supermodule' \
+'test_create_repo super && cd super &&
+echo file > file &&
+git add file &&
+git commit -m B-super-initial'
+
+cd "$base_dir"
+
+test_expect_success 'submodule add --reference' \
+'cd super && git submodule add --reference ../B "file://$base_dir/A" sub &&
+git commit -m B-super-added'
+
+cd "$base_dir"
+
+test_expect_success 'after add: existence of info/alternates' \
+'test `wc -l <super/sub/.git/objects/info/alternates` = 1'
+
+cd "$base_dir"
+
+test_expect_success 'that reference gets used with add' \
+'cd super/sub &&
+echo "0 objects, 0 kilobytes" > expected &&
+git count-objects > current &&
+diff expected current'
+
+cd "$base_dir"
+
+test_expect_success 'cloning supermodule' \
+'git clone super super-clone'
+
+cd "$base_dir"
+
+test_expect_success 'update with reference' \
+'cd super-clone && git submodule update --init --reference ../B'
+
+cd "$base_dir"
+
+test_expect_success 'after update: existence of info/alternates' \
+'test `wc -l <super-clone/sub/.git/objects/info/alternates` = 1'
+
+cd "$base_dir"
+
+test_expect_success 'that reference gets used with update' \
+'cd super-clone/sub &&
+echo "0 objects, 0 kilobytes" > expected &&
+git count-objects > current &&
+diff expected current'
+
+cd "$base_dir"
+
+test_done