From 746dbec296cb50d1ded5e481cc6bad1903c098cc Mon Sep 17 00:00:00 2001
From: Steven Easter <seaster@levelsbeyond.com>
Date: Mon, 1 Jun 2015 10:19:28 -0600
Subject: [PATCH] fix(ngOptions): use reference check only when not using
 trackBy

Change the check on changed value for ngOptions to ensure that a reference check is only done
when trackBy is not used.  Previously, if trackBy was being used but the values of the objects were
equal a reference check was then used which would cause the check to be true if the objects had
different memory references but the values were equal.  This can cause issues with forms being
marked dirty when the value of the model as not actually changed.

Closes #11936
---
 src/ng/directive/ngOptions.js      |  3 +--
 test/ng/directive/ngOptionsSpec.js | 20 ++++++++++++++++++++
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/src/ng/directive/ngOptions.js b/src/ng/directive/ngOptions.js
index 6364f0cf6d55..2498042579d6 100644
--- a/src/ng/directive/ngOptions.js
+++ b/src/ng/directive/ngOptions.js
@@ -706,8 +706,7 @@ var ngOptionsDirective = ['$compile', '$parse', function($compile, $parse) {
         // Check to see if the value has changed due to the update to the options
         if (!ngModelCtrl.$isEmpty(previousValue)) {
           var nextValue = selectCtrl.readValue();
-          if (ngOptions.trackBy && !equals(previousValue, nextValue) ||
-                previousValue !== nextValue) {
+          if (ngOptions.trackBy ? !equals(previousValue, nextValue) : previousValue !== nextValue) {
             ngModelCtrl.$setViewValue(nextValue);
             ngModelCtrl.$render();
           }
diff --git a/test/ng/directive/ngOptionsSpec.js b/test/ng/directive/ngOptionsSpec.js
index 399d64392175..33cdfb00ce38 100644
--- a/test/ng/directive/ngOptionsSpec.js
+++ b/test/ng/directive/ngOptionsSpec.js
@@ -1176,6 +1176,26 @@ describe('ngOptions', function() {
 
     });
 
+    it('should not set view value again if the tracked property of the model has not changed when using trackBy', function() {
+
+      createSelect({
+        'ng-model': 'selected',
+        'ng-options': 'item for item in arr track by item.id'
+      });
+
+      scope.$apply(function() {
+        scope.selected = {id: 10, label: 'ten'};
+      });
+
+      spyOn(element.controller('ngModel'), '$setViewValue');
+
+      scope.$apply(function() {
+        scope.arr[0] = {id: 10, label: 'ten'};
+      });
+
+      expect(element.controller('ngModel').$setViewValue).not.toHaveBeenCalled();
+    });
+
     it('should not re-render if a property of the model is changed when not using trackBy', function() {
 
       createSelect({