diff --git a/test/interval.t.cpp b/test/interval.t.cpp
index 4c3b3bdb..153ebee5 100644
--- a/test/interval.t.cpp
+++ b/test/interval.t.cpp
@@ -31,7 +31,7 @@
 ////////////////////////////////////////////////////////////////////////////////
 int main (int, char**)
 {
-  UnitTest t (36);
+  UnitTest t (38);
 
   // bool isStarted () const;
   // bool isEnded () const;
@@ -162,6 +162,11 @@ int main (int, char**)
   t.is (i19.json (), "{\"start\":\"19700101T000001Z\",\"end\":\"19700101T000002Z\",\"tags\":[\"Trans-Europe Express\",\"bar\",\"foo\"]}",
                "JSON '{\"start\":\"19700101T000001Z\",\"end\":\"19700101T000002Z\",\"tags\":[\"Trans-Europe Express\",\"bar\",\"foo\"]}'");
 
+  Interval i20;
+  i20.tag ("foo");
+  t.ok    (i20.hasTag ("foo"), "hasTag positive");
+  t.notok (i20.hasTag ("bar"), "hasTag negative");
+
   return 0;
 }