Fixed bug with calling callback several times when some functions were executed in parallel.

1 files changed, 1 insertions, 0 deletions

diff --git a/lib/async.js b/lib/async.js
index bd44a06..d5fe445 100644
--- a/lib/async.js
+++ b/lib/async.js
@@ -347,6 +347,7 @@
         addListener(function () {
             if (completed.length === keys.length) {
                 callback(null);
+                callback = function () {};
             }
         });