1 files changed, 8 insertions, 0 deletions
diff --git a/support/es.test.js b/support/es.test.js
index 9f7fd5e..da008fa 100644
--- a/support/es.test.js
+++ b/support/es.test.js
@@ -1,6 +1,7 @@
 // simple async example to test ES module build output
 
 import {waterfall as waterfall} from  "../build-es/index";
+import {wrapSync} from  "../build-es/index";
 import async from "../build-es/index";
 import constant from "../build-es/constant";
 
@@ -10,6 +11,13 @@ waterfall([
         async.setImmediate(function () {
             next(null, val);
         });
+    },
+    wrapSync(function (a) { return a; }),
+    function (val, next) {
+        async.forEachOf({a: 1}, function (val, key, cb) {
+            if (val !== 1 && key !== 'a') return cb(new Error('fail!'));
+            cb();
+        }, function (err) { next (err, val)});
     }
 ], function (err, result) {
     if (err) { throw err; }