Merge pull request #406 from imajus/bugfix/event-handlers-reactive-loop

Stop establishing unnecessary reactive dependencies

packages/blaze/template.js

@@ -530,14 +530,18 @@ Template.prototype.events = function (eventMap) {
     eventMap2[k] = (function (k, v) {
       return function (event /*, ...*/) {
         var view = this; // passed by EventAugmenter
-        var data = Blaze.getData(event.currentTarget);
-        if (data == null) data = {};
         var args = Array.prototype.slice.call(arguments);
-        var tmplInstanceFunc = Blaze._bind(view.templateInstance, view);
-        args.splice(1, 0, tmplInstanceFunc());
-
-        return Template._withTemplateInstanceFunc(tmplInstanceFunc, function () {
-          return v.apply(data, args);
+        // Exiting the current computation to avoid creating unnecessary
+        // and unexpected reactive dependencies with Templates data
+        // or any other reactive dependencies defined in event handlers
+        return Tracker.nonreactive(function () {
+          var data = Blaze.getData(event.currentTarget);
+          if (data == null) data = {};
+          var tmplInstanceFunc = Blaze._bind(view.templateInstance, view);
+          args.splice(1, 0, tmplInstanceFunc());
+          return Template._withTemplateInstanceFunc(tmplInstanceFunc, function () {
+            return v.apply(data, args);
+          });
         });
       };
     })(k, eventMap[k]);