Merge branch 'pk/subsub-fetch-fix'

"git fetch" did not work correctly with nested submodules where the
innermost submodule that is not of interest got updated in the
upstream, which has been corrected.

* pk/subsub-fetch-fix:
  submodules: fix of regression on fetching of non-init subsub-repo

t/t5526-fetch-submodules.sh

@@ -719,4 +719,67 @@ test_expect_success 'fetch new submodule commit intermittently referenced by sup
 	)
 '
 
+add_commit_push () {
+	dir="$1"
+	msg="$2"
+	shift 2
+	git -C "$dir" add "$@" &&
+	git -C "$dir" commit -a -m "$msg" &&
+	git -C "$dir" push
+}
+
+compare_refs_in_dir () {
+	fail= &&
+	if test "x$1" = 'x!'
+	then
+		fail='!' &&
+		shift
+	fi &&
+	git -C "$1" rev-parse --verify "$2" >expect &&
+	git -C "$3" rev-parse --verify "$4" >actual &&
+	eval $fail test_cmp expect actual
+}
+
+
+test_expect_success 'setup nested submodule fetch test' '
+	# does not depend on any previous test setups
+
+	for repo in outer middle inner
+	do
+		(
+			git init --bare $repo &&
+			git clone $repo ${repo}_content &&
+			echo "$repo" >"${repo}_content/file" &&
+			add_commit_push ${repo}_content "initial" file
+		) || return 1
+	done &&
+
+	git clone outer A &&
+	git -C A submodule add "$pwd/middle" &&
+	git -C A/middle/ submodule add "$pwd/inner" &&
+	add_commit_push A/middle/ "adding inner sub" .gitmodules inner &&
+	add_commit_push A/ "adding middle sub" .gitmodules middle &&
+
+	git clone outer B &&
+	git -C B/ submodule update --init middle &&
+
+	compare_refs_in_dir A HEAD B HEAD &&
+	compare_refs_in_dir A/middle HEAD B/middle HEAD &&
+	test -f B/file &&
+	test -f B/middle/file &&
+	! test -f B/middle/inner/file &&
+
+	echo "change on inner repo of A" >"A/middle/inner/file" &&
+	add_commit_push A/middle/inner "change on inner" file &&
+	add_commit_push A/middle "change on inner" inner &&
+	add_commit_push A "change on inner" middle
+'
+
+test_expect_success 'fetching a superproject containing an uninitialized sub/sub project' '
+	# depends on previous test for setup
+
+	git -C B/ fetch &&
+	compare_refs_in_dir A origin/master B origin/master
+'
+
 test_done