diff --git a/java/debugger.jpda.truffle/test/unit/src/org/netbeans/modules/debugger/jpda/truffle/JPDATestCase.java b/java/debugger.jpda.truffle/test/unit/src/org/netbeans/modules/debugger/jpda/truffle/JPDATestCase.java
index b22939ab99be..0d2c43a2273c 100644
--- a/java/debugger.jpda.truffle/test/unit/src/org/netbeans/modules/debugger/jpda/truffle/JPDATestCase.java
+++ b/java/debugger.jpda.truffle/test/unit/src/org/netbeans/modules/debugger/jpda/truffle/JPDATestCase.java
@@ -109,6 +109,7 @@ private void run(JPDASupport support, ThrowableConsumer<JPDASupport> supportCons
     }
 
     protected TruffleStackFrame checkStoppedAtScript(JPDAThread thread, String sourcePath, int line) {
+        assertNotNull("JPDAThread was null while testing: "+sourcePath, thread);
         CurrentPCInfo currentPCInfo = TruffleAccess.getCurrentPCInfo(thread);
         assertNotNull("Missing CurrentPCInfo, suspended at " + thread.getClassName() + "." + thread.getMethodName(), currentPCInfo);
         TruffleStackFrame topFrame = currentPCInfo.getTopFrame();