git-submodule --cached status | grep "^+$rev1"
'
+test_expect_success 'git diff should report the SHA1 of the new submodule commit' '
+ git-diff | grep "^+Subproject commit $rev2"
+'
+
test_expect_success 'update should checkout rev1' '
git-submodule update &&
head=$(cd lib && git rev-parse HEAD) &&