diff --git a/quic/test_tools/quic_session_peer.h b/quic/test_tools/quic_session_peer.h
index 5a58360..ffb6a46 100644
--- a/quic/test_tools/quic_session_peer.h
+++ b/quic/test_tools/quic_session_peer.h
@@ -81,6 +81,7 @@
                                          QuicStreamId stream_id);
   static void set_is_configured(QuicSession* session, bool value);
   static void SetPerspective(QuicSession* session, Perspective perspective);
+  static size_t GetNumOpenDynamicStreams(QuicSession* session);
 };
 
 }  // namespace test