Make stash and checkout ignore contained repos

To emulate git, stash should not remove untracked git repositories
inside the parent repo, and checkout's REMOVE_UNTRACKED should
also skip over these items.

`git stash` actually prints a warning message for these items.
That should be possible with a checkout notify callback if you
wanted to, although it would require a bit of extra logic as things
are at the moment.

2 files changed, 21 insertions, 9 deletions

diff --git a/tests/stash/save.c b/tests/stash/save.c
index f06c1fb71..5165eeadf 100644
--- a/tests/stash/save.c
+++ b/tests/stash/save.c
@@ -342,7 +342,7 @@ void test_stash_save__can_stage_normal_then_stage_untracked(void)
 
 void test_stash_save__including_untracked_without_any_untracked_file_creates_an_empty_tree(void)
 {
-	cl_git_pass(p_unlink("stash/when"));
+	cl_must_pass(p_unlink("stash/when"));
 
 	assert_status(repo, "what", GIT_STATUS_WT_MODIFIED | GIT_STATUS_INDEX_MODIFIED);
 	assert_status(repo, "how", GIT_STATUS_INDEX_MODIFIED);
@@ -354,3 +354,18 @@ void test_stash_save__including_untracked_without_any_untracked_file_creates_an_
 
 	assert_object_oid("stash^3^{tree}", EMPTY_TREE, GIT_OBJ_TREE);
 }
+
+void test_stash_save__skip_submodules(void)
+{
+	git_repository *untracked_repo;
+	cl_git_pass(git_repository_init(&untracked_repo, "stash/untracked_repo", false));
+	cl_git_mkfile("stash/untracked_repo/content", "stuff");
+	git_repository_free(untracked_repo);
+
+	assert_status(repo, "untracked_repo/", GIT_STATUS_WT_NEW);
+
+	cl_git_pass(git_stash_save(
+		&stash_tip_oid, repo, signature, NULL, GIT_STASH_INCLUDE_UNTRACKED));
+
+	assert_status(repo, "untracked_repo/", GIT_STATUS_WT_NEW);
+}
diff --git a/tests/stash/stash_helpers.c b/tests/stash/stash_helpers.c
index 8b7d685f8..29cb25c5f 100644
--- a/tests/stash/stash_helpers.c
+++ b/tests/stash/stash_helpers.c
@@ -44,13 +44,10 @@ void assert_status(
 	unsigned int status;
 	int error;
 
-	error = git_status_file(&status, repo, path);
-
-	if (status_flags < 0) {
-		cl_assert_equal_i(status_flags, error);
-		return;
+	if (status_flags < 0)
+		cl_assert_equal_i(status_flags, git_status_file(&status, repo, path));
+	else {
+		cl_git_pass(git_status_file(&status, repo, path));
+		cl_assert_equal_i((unsigned int)status_flags, status);
 	}
-
-	cl_assert_equal_i(0, error);
-	cl_assert_equal_i((unsigned int)status_flags, status);
 }