diff --git a/Utils/async_utils.dart b/Utils/async_utils.dart
index 4132446..29bb5e1 100644
--- a/Utils/async_utils.dart
+++ b/Utils/async_utils.dart
@@ -2,7 +2,6 @@
 
 import "dart:async";
 export "dart:async";
-import "expect.dart";
 
 const ONE_MS = const Duration(milliseconds: 1);
 
@@ -56,7 +55,9 @@
 
 void  asyncEnd() {
 //  print("asyncEnd");
-  Expect.isFalse(_asyncCounter == 0, "asyncEnd: _asyncCounter==0");
+  if (_asyncCounter == 0) {
+    throw new Exception("_asyncCounter==0");
+  }
   _asyncCounter--;
   if (_asyncCounter == 0) {
     print("unittest-suite-success");