updating tests to allow for issue 496 resolution

Author: Garison Draper

stacker/context.py

@@ -99,6 +99,8 @@ def tags(self):
         if tags is not None:
             if "stacker_namespace" in tags:
                 return tags
+            if tags == {}:
+                return {}
             tags["stacker_namespace"] = self.namespace
             return tags
         if self.namespace:

stacker/tests/test_stack.py

@@ -80,7 +80,8 @@ def test_stack_tags_default(self):
             stack_id=1
         )
         stack = Stack(definition=definition, context=self.context)
-        self.assertEquals(stack.tags, {"environment": "prod"})
+        self.assertEquals(stack.tags, {"environment": "prod",
+                                       "stacker_namespace": u"namespace"})
 
     def test_stack_tags_override(self):
         self.config.tags = {"environment": "prod"}
@@ -90,17 +91,20 @@ def test_stack_tags_override(self):
             tags={"environment": "stage"}
         )
         stack = Stack(definition=definition, context=self.context)
-        self.assertEquals(stack.tags, {"environment": "stage"})
+        self.assertEquals(stack.tags, {"environment": "stage",
+                                       'stacker_namespace': u'namespace'})
 
     def test_stack_tags_extra(self):
-        self.config.tags = {"environment": "prod"}
+        self.config.tags = {"environment": "prod",
+                            "stacker_namespace": u"namespace"}
         definition = generate_definition(
             base_name="vpc",
             stack_id=1,
             tags={"app": "graph"}
         )
         stack = Stack(definition=definition, context=self.context)
-        self.assertEquals(stack.tags, {"environment": "prod", "app": "graph"})
+        self.assertEquals(stack.tags, {"environment": "prod", "app": "graph",
+                                       "stacker_namespace": u"namespace"})
 
 
 if __name__ == '__main__':