1 files changed, 11 insertions, 0 deletions
diff --git a/indra/llcommon/tests/listener.h b/indra/llcommon/tests/listener.h
index 9c5c18a150..6072060bb6 100644
--- a/indra/llcommon/tests/listener.h
+++ b/indra/llcommon/tests/listener.h
@@ -138,4 +138,15 @@ struct Collect
     StringVec result;
 };
 
+struct Concat
+{
+    bool operator()(const LLSD& event)
+    {
+        result += event.asString();
+        return false;
+    }
+    void clear() { result.clear(); }
+    std::string result;
+};
+
 #endif /* ! defined(LL_LISTENER_H) */