Fix #2846 nested "change" events trigger with correct options

backbone.js

@@ -350,7 +350,7 @@
 
       // Trigger all relevant attribute changes.
       if (!silent) {
-        if (changes.length) this._pending = true;
+        if (changes.length) this._pending = options;
         for (var i = 0, l = changes.length; i < l; i++) {
           this.trigger('change:' + changes[i], this, current[changes[i]], options);
         }
@@ -361,6 +361,7 @@
       if (changing) return this;
       if (!silent) {
         while (this._pending) {
+          options = this._pending;
           this._pending = false;
           this.trigger('change', this, options);
         }

test/model.js

@@ -262,6 +262,26 @@
     model.set({result: void 0});
   });
 
+  test("nested set triggers with the correct options", function() {
+    var model = new Backbone.Model();
+    var o1 = {};
+    var o2 = {};
+    var o3 = {};
+    model.on('change', function(__, options) {
+      switch (model.get('a')) {
+      case 1:
+        equal(options, o1);
+        return model.set('a', 2, o2);
+      case 2:
+        equal(options, o2);
+        return model.set('a', 3, o3);
+      case 3:
+        equal(options, o3);
+      }
+    });
+    model.set('a', 1, o1);
+  });
+
   test("multiple unsets", 1, function() {
     var i = 0;
     var counter = function(){ i++; };