1 files changed, 77 insertions, 0 deletions
diff --git a/third_party/git/t/t7410-submodule-checkout-to.sh b/third_party/git/t/t7410-submodule-checkout-to.sh
new file mode 100755
index 000000000000..f1b492ebc46a
--- /dev/null
+++ b/third_party/git/t/t7410-submodule-checkout-to.sh
@@ -0,0 +1,77 @@
+#!/bin/sh
+
+test_description='Combination of submodules and multiple workdirs'
+
+. ./test-lib.sh
+
+base_path=$(pwd -P)
+
+test_expect_success 'setup: make origin'  '
+	mkdir -p origin/sub &&
+	(
+		cd origin/sub && git init &&
+		echo file1 >file1 &&
+		git add file1 &&
+		git commit -m file1
+	) &&
+	mkdir -p origin/main &&
+	(
+		cd origin/main && git init &&
+		git submodule add ../sub &&
+		git commit -m "add sub"
+	) &&
+	(
+		cd origin/sub &&
+		echo file1updated >file1 &&
+		git add file1 &&
+		git commit -m "file1 updated"
+	) &&
+	git -C origin/main/sub pull &&
+	(
+		cd origin/main &&
+		git add sub &&
+		git commit -m "sub updated"
+	)
+'
+
+test_expect_success 'setup: clone' '
+	mkdir clone &&
+	git -C clone clone --recursive "$base_path/origin/main"
+'
+
+rev1_hash_main=$(git --git-dir=origin/main/.git show --pretty=format:%h -q "HEAD~1")
+rev1_hash_sub=$(git --git-dir=origin/sub/.git show --pretty=format:%h -q "HEAD~1")
+
+test_expect_success 'checkout main' '
+	mkdir default_checkout &&
+	git -C clone/main worktree add "$base_path/default_checkout/main" "$rev1_hash_main"
+'
+
+test_expect_failure 'can see submodule diffs just after checkout' '
+	git -C default_checkout/main diff --submodule master"^!" >out &&
+	grep "file1 updated" out
+'
+
+test_expect_success 'checkout main and initialize independent clones' '
+	mkdir fully_cloned_submodule &&
+	git -C clone/main worktree add "$base_path/fully_cloned_submodule/main" "$rev1_hash_main" &&
+	git -C fully_cloned_submodule/main submodule update
+'
+
+test_expect_success 'can see submodule diffs after independent cloning' '
+	git -C fully_cloned_submodule/main diff --submodule master"^!" >out &&
+	grep "file1 updated" out
+'
+
+test_expect_success 'checkout sub manually' '
+	mkdir linked_submodule &&
+	git -C clone/main worktree add "$base_path/linked_submodule/main" "$rev1_hash_main" &&
+	git -C clone/main/sub worktree add "$base_path/linked_submodule/main/sub" "$rev1_hash_sub"
+'
+
+test_expect_success 'can see submodule diffs after manual checkout of linked submodule' '
+	git -C linked_submodule/main diff --submodule master"^!" >out &&
+	grep "file1 updated" out
+'
+
+test_done