fix(ngRepeat): correctly track elements even when the collection is initially undefined

Previously if the collection model was set to undefined on the first digest,
the repeater would get confused and not use the correct tracking function
for associating model with dom elements in the repeater.

Closes #4145
Closes #3964

1 files changed, 20 insertions, 2 deletions

diff --git a/test/ng/directive/ngRepeatSpec.js b/test/ng/directive/ngRepeatSpec.js
index fc41bc6d..72035566 100644
--- a/test/ng/directive/ngRepeatSpec.js
+++ b/test/ng/directive/ngRepeatSpec.js
@@ -841,6 +841,26 @@ describe('ngRepeat', function() {
       expect(newLis[1]).toEqual(lis[0]);
       expect(newLis[2]).toEqual(lis[1]);
     });
+
+    it('should be stable even if the collection is initially undefined', function () {
+      scope.items = undefined;
+      scope.$digest();
+
+      scope.items = [
+        { name: 'A' },
+        { name: 'B' },
+        { name: 'C' }
+      ];
+      scope.$digest();
+
+      lis = element.find('li');
+      scope.items.shift();
+      scope.$digest();
+
+      var newLis = element.find('li');
+      expect(newLis.length).toBe(2);
+      expect(newLis[0]).toBe(lis[1]);
+    });
   });
 
   it('should grow multi-node repeater', inject(function($compile, $rootScope) {
@@ -861,8 +881,6 @@ describe('ngRepeat', function() {
     $rootScope.$digest();
     expect(element.text()).toEqual('T1:D1;T2:D2;T3:D3;');
   }));
-
-
 });
 
 describe('ngRepeat animations', function() {