From 6817c89133d8c6cd38ac5245dd94af98578f45e6 Mon Sep 17 00:00:00 2001
From: Caitlin Potter <caitpotter88@gmail.com>
Date: Wed, 20 Aug 2014 21:22:19 -0400
Subject: [PATCH] fix(copy): clear array destinations correctly for non-array
 sources

Closes #8610
---
 src/Angular.js      | 1 +
 test/AngularSpec.js | 6 ++++++
 2 files changed, 7 insertions(+)

diff --git a/src/Angular.js b/src/Angular.js
index 1a17f73d01a2..593c6e4fa4b1 100644
--- a/src/Angular.js
+++ b/src/Angular.js
@@ -803,6 +803,7 @@ function copy(source, destination, stackSource, stackDest) {
       forEach(destination, function(value, key) {
         delete destination[key];
       });
+      if (isArray(destination)) destination.length = 0;
       for ( var key in source) {
         if(source.hasOwnProperty(key)) {
           result = copy(source[key], null, stackSource, stackDest);
diff --git a/test/AngularSpec.js b/test/AngularSpec.js
index 72299380688a..8a8bd1ca845f 100644
--- a/test/AngularSpec.js
+++ b/test/AngularSpec.js
@@ -184,6 +184,12 @@ describe('angular', function() {
       expect(aCopy).toBe(aCopy.self);
       expect(aCopy.selfs[2]).not.toBe(a.selfs[2]);
     });
+
+    it('should clear destination arrays correctly when source is non-array', function() {
+      expect(copy(null, [1,2,3])).toEqual([]);
+      expect(copy(undefined, [1,2,3])).toEqual([]);
+      expect(copy({0: 1, 1: 2}, [1,2,3])).toEqual([1,2]);
+    });
   });
 
   describe("extend", function() {