From 26207db6fd22aaeaf184fbc8b6607d7090a8b85d Mon Sep 17 00:00:00 2001
From: Gonzalo Ruiz de Villa <gonzalo.ruizdevilla@adesis.com>
Date: Wed, 1 May 2013 00:19:14 +0200
Subject: [PATCH] fix(input): detect changes in array when its values are
 changed

When model value is an array, its values must be stored in a new array
to allow a comparison between old and new values when checking
if a value is out of sync with the model.

Closes #1751
---
 src/ng/directive/input.js      | 32 +++++++++++++++++++++++++++-----
 test/ng/directive/inputSpec.js | 14 ++++++++++++++
 2 files changed, 41 insertions(+), 5 deletions(-)

diff --git a/src/ng/directive/input.js b/src/ng/directive/input.js
index 8ab6f696ca81..60f52d07e37f 100644
--- a/src/ng/directive/input.js
+++ b/src/ng/directive/input.js
@@ -1006,6 +1006,29 @@ var NgModelController = ['$scope', '$exceptionHandler', '$attrs', '$element', '$
     $element.removeClass(DIRTY_CLASS).addClass(PRISTINE_CLASS);
   };
 
+  var ctrl = this;
+
+  function outOfSyncWithModel(value) {
+    if (ctrl.$modelValue !== value) {
+      return true;
+    }
+    if (isArray(value)) {
+      return !equals(ctrl.$modelArrayValues, value);
+    }
+    return false;
+  }
+
+  function storeArrayValues(value) {
+    ctrl.$modelArrayValues = [].concat(value);
+  }
+
+  function storeValue(value) {
+    ctrl.$modelValue = value;
+    if (isArray(value)) {
+      storeArrayValues(value);
+    }
+  }
+
   /**
    * @ngdoc function
    * @name ng.directive:ngModel.NgModelController#$setViewValue
@@ -1039,7 +1062,7 @@ var NgModelController = ['$scope', '$exceptionHandler', '$attrs', '$element', '$
     });
 
     if (this.$modelValue !== value) {
-      this.$modelValue = value;
+      storeValue(value);
       ngModelSet($scope, value);
       forEach(this.$viewChangeListeners, function(listener) {
         try {
@@ -1052,18 +1075,17 @@ var NgModelController = ['$scope', '$exceptionHandler', '$attrs', '$element', '$
   };
 
   // model -> value
-  var ctrl = this;
 
   $scope.$watch(function ngModelWatch() {
     var value = ngModelGet($scope);
 
-    // if scope model value and ngModel value are out of sync
-    if (ctrl.$modelValue !== value) {
+    if (outOfSyncWithModel(value)) {
 
       var formatters = ctrl.$formatters,
           idx = formatters.length;
 
-      ctrl.$modelValue = value;
+      storeValue(value);
+
       while(idx--) {
         value = formatters[idx](value);
       }
diff --git a/test/ng/directive/inputSpec.js b/test/ng/directive/inputSpec.js
index f8898074f13e..4a89dd7292d4 100644
--- a/test/ng/directive/inputSpec.js
+++ b/test/ng/directive/inputSpec.js
@@ -990,6 +990,20 @@ describe('input', function() {
     });
 
 
+    it("should detect changes in the values of an array", function () {
+      var list = ['x', 'y', 'z'];
+      compileInput('<input type="text" ng-model="list" ng-list />');
+      scope.$apply(function() {
+        scope.list = list;
+      });
+      expect(inputElm.val()).toBe('x, y, z');
+      scope.$apply(function() {
+        list.unshift('w');
+      });
+      expect(inputElm.val()).toBe('w, x, y, z');
+    });
+
+
     xit('should require at least one item', function() {
       compileInput('<input type="text" ng-model="list" ng-list required />');