Fixes listenToOnce memory leak.

baig · Nov 3, 2014 · 459dc24 · 459dc24
1 parent 71cecdc
commit 459dc24
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Showing 2 changed files with 19 additions and 1 deletion.
diff --git a/backbone.js b/backbone.js
@@ -239,6 +239,13 @@
       var id = obj._listenId || (obj._listenId = _.uniqueId('l'));
       listeningTo[id] = obj;
       if (!callback && typeof name === 'object') callback = this;
+      if (implementation === 'once') {
+        var cb = callback;
+        callback = function () {
+          this.stopListening.apply(this, _.rest(arguments));
+          return cb.apply(this, arguments);
+        };
+      }
       obj[implementation](name, callback, this);
       return this;
     };

diff --git a/test/events.js b/test/events.js
@@ -177,14 +177,25 @@
     equal(_.keys(a._listeningTo).length, 0);
   });
 
-  test("listenToOnce cleans up references after the event has fired", 2, function() {
+  test("listenToOnce without context cleans up references after the event has fired", 2, function() {
     var a = _.extend({}, Backbone.Events);
     var b = _.extend({}, Backbone.Events);
     a.listenToOnce(b, 'all', function(){ ok(true); });
     b.trigger('anything');
     equal(_.keys(a._listeningTo).length, 0);
   });
 
+  test("listenToOnce with event maps cleans up references", 2, function() {
+    var a = _.extend({}, Backbone.Events);
+    var b = _.extend({}, Backbone.Events);
+    a.listenToOnce(b, {
+      a: function() { ok(true); },
+      b: function() { ok(false); }
+    });
+    b.trigger('a');
+    equal(_.keys(a._listeningTo).length, 1);
+  });
+
   test("listenTo with empty callback doesn't throw an error", 1, function(){
     var e = _.extend({}, Backbone.Events);
     e.listenTo(e, "foo", null);