From 04596e8aa02088896bd1be090d208646dbe84dc1 Mon Sep 17 00:00:00 2001
From: Ryan Niemeyer <rniemeyer@gmail.com>
Date: Wed, 8 Apr 2015 13:51:45 -0500
Subject: [PATCH] Component defaultLoader should use hasOwnProperty for
 isRegistered check

---
 spec/components/defaultLoaderBehaviors.js | 8 ++++++++
 src/components/defaultLoader.js           | 8 ++++----
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/spec/components/defaultLoaderBehaviors.js b/spec/components/defaultLoaderBehaviors.js
index 352e1b25c..a927f3f20 100644
--- a/spec/components/defaultLoaderBehaviors.js
+++ b/spec/components/defaultLoaderBehaviors.js
@@ -18,6 +18,14 @@ describe('Components: Default loader', function() {
         expect(ko.components.isRegistered(testComponentName)).toBe(false);
     });
 
+    it('Allows registering component names that may conflict with properties on Object.prototype', function() {
+        var prototypeProperty = 'toString';
+
+        expect(ko.components.isRegistered(prototypeProperty)).toBe(false);
+        ko.components.register(prototypeProperty, {});
+        expect(ko.components.isRegistered(prototypeProperty)).toBe(true);
+    });
+
     it('Throws if you try to register a component that is already registered', function() {
         ko.components.register(testComponentName, {});
 
diff --git a/src/components/defaultLoader.js b/src/components/defaultLoader.js
index 1169a4b7d..2db2cf529 100644
--- a/src/components/defaultLoader.js
+++ b/src/components/defaultLoader.js
@@ -22,16 +22,16 @@
         }
 
         defaultConfigRegistry[componentName] = config;
-    }
+    };
 
     ko.components.isRegistered = function(componentName) {
-        return componentName in defaultConfigRegistry;
-    }
+        return defaultConfigRegistry.hasOwnProperty(componentName);
+    };
 
     ko.components.unregister = function(componentName) {
         delete defaultConfigRegistry[componentName];
         ko.components.clearCachedDefinition(componentName);
-    }
+    };
 
     ko.components.defaultLoader = {
         'getConfig': function(componentName, callback) {