1 files changed, 60 insertions, 0 deletions
diff --git a/t/t4027-diff-submodule.sh b/t/t4027-diff-submodule.sh
new file mode 100755
index 0000000000..ba6679c6e4
--- /dev/null
+++ b/t/t4027-diff-submodule.sh
@@ -0,0 +1,60 @@
+#!/bin/sh
+
+test_description='difference in submodules'
+
+. ./test-lib.sh
+. ../diff-lib.sh
+
+_z40=0000000000000000000000000000000000000000
+test_expect_success setup '
+	test_tick &&
+	test_create_repo sub &&
+	(
+		cd sub &&
+		echo hello >world &&
+		git add world &&
+		git commit -m submodule
+	) &&
+
+	test_tick &&
+	echo frotz >nitfol &&
+	git add nitfol sub &&
+	git commit -m superproject &&
+
+	(
+		cd sub &&
+		echo goodbye >world &&
+		git add world &&
+		git commit -m "submodule #2"
+	) &&
+
+	set x $(
+		cd sub &&
+		git rev-list HEAD
+	) &&
+	echo ":160000 160000 $3 $_z40 M	sub" >expect
+'
+
+test_expect_success 'git diff --raw HEAD' '
+	git diff --raw --abbrev=40 HEAD >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'git diff-index --raw HEAD' '
+	git diff-index --raw HEAD >actual.index &&
+	test_cmp expect actual.index
+'
+
+test_expect_success 'git diff-files --raw' '
+	git diff-files --raw >actual.files &&
+	test_cmp expect actual.files
+'
+
+test_expect_success 'git diff (empty submodule dir)' '
+	: >empty &&
+	rm -rf sub/* sub/.git &&
+	git diff > actual.empty &&
+	test_cmp empty actual.empty
+'
+
+test_done