tests: submodule git lookup can be dupped test has been added.

tests/submodule/lookup.c

@@ -42,6 +42,46 @@ void test_submodule_lookup__simple_lookup(void)
 	assert_submodule_exists(g_repo, "sm_added_and_uncommited/");
 }
 
+void test_submodule_lookup__can_be_dupped(void)
+{
+	git_submodule *sm;
+	git_submodule *sm_duplicate;
+	const char *oid = "480095882d281ed676fe5b863569520e54a7d5c0";
+
+	// Check original
+	cl_git_pass(git_submodule_lookup(&sm, g_repo, "sm_unchanged"));
+	cl_assert(git_submodule_owner(sm) == g_repo);
+	cl_assert_equal_s("sm_unchanged", git_submodule_name(sm));
+	cl_assert(git__suffixcmp(git_submodule_path(sm), "sm_unchanged") == 0);
+	cl_assert(git__suffixcmp(git_submodule_url(sm), "/submod2_target") == 0);
+
+	cl_assert(git_oid_streq(git_submodule_index_id(sm), oid) == 0);
+	cl_assert(git_oid_streq(git_submodule_head_id(sm), oid) == 0);
+	cl_assert(git_oid_streq(git_submodule_wd_id(sm), oid) == 0);
+
+	cl_assert(git_submodule_ignore(sm) == GIT_SUBMODULE_IGNORE_NONE);
+	cl_assert(git_submodule_update_strategy(sm) == GIT_SUBMODULE_UPDATE_CHECKOUT);
+
+	// Duplicate and free original
+	cl_assert(git_submodule_dup(&sm_duplicate, sm) == 0);
+	git_submodule_free(sm);
+
+	// Check duplicate
+	cl_assert(git_submodule_owner(sm_duplicate) == g_repo);
+	cl_assert_equal_s("sm_unchanged", git_submodule_name(sm_duplicate));
+	cl_assert(git__suffixcmp(git_submodule_path(sm_duplicate), "sm_unchanged") == 0);
+	cl_assert(git__suffixcmp(git_submodule_url(sm_duplicate), "/submod2_target") == 0);
+
+	cl_assert(git_oid_streq(git_submodule_index_id(sm_duplicate), oid) == 0);
+	cl_assert(git_oid_streq(git_submodule_head_id(sm_duplicate), oid) == 0);
+	cl_assert(git_oid_streq(git_submodule_wd_id(sm_duplicate), oid) == 0);
+
+	cl_assert(git_submodule_ignore(sm_duplicate) == GIT_SUBMODULE_IGNORE_NONE);
+	cl_assert(git_submodule_update_strategy(sm_duplicate) == GIT_SUBMODULE_UPDATE_CHECKOUT);
+
+	git_submodule_free(sm_duplicate);
+}
+
 void test_submodule_lookup__accessors(void)
 {
 	git_submodule *sm;