diff --git a/tests/mock/sysrepo_subscription.cpp b/tests/mock/sysrepo_subscription.cpp
index c74d7af..ba276a7 100644
--- a/tests/mock/sysrepo_subscription.cpp
+++ b/tests/mock/sysrepo_subscription.cpp
@@ -6,6 +6,8 @@
  *
 */
 
+#include <experimental/iterator>
+#include <sstream>
 #include <sysrepo-cpp/Session.hpp>
 #include "sysrepo_subscription.hpp"
 
@@ -94,6 +96,14 @@
         v->set(xpath.c_str(), what.c_str());
     }
 
+    void operator()(const bits_& what)
+    {
+        std::stringstream ss;
+        std::copy(what.m_bits.begin(), what.m_bits.end(), std::experimental::make_ostream_joiner(ss, " "));
+        v->set(xpath.c_str(), ss.str().c_str());
+
+    }
+
     template <typename Type>
     void operator()(const Type what)
     {